Differences in adaptation/Status of women

::This is a sub-page branching off from the main article on "Gender and sexuality"
The TV series has not shown women holding and wielding political power in the Seven Kingdoms as frequently as it occurs in the novels, which makes them appear to have less agency. 
==The social status of women from major vassal Houses - in the novels==
The TV series does present Queen Cersei Lannister as wielding political power in King's Landing, or Daenerys Targaryen becoming Queen of Meereen through conquest on the eastern continent, and the two of them do occupy a large mount of "screen time" - but as individuals, they are only exceptional and isolated cases. "Frequency" of showing women wielding political power in this context does not refer to how many chapters of the books or episodes of the TV series focus on Cersei and Daenerys's activities, but on the overall number of female characters who are presented holding political power - which reflects the overall status of women in Westeros's society. 
During the course of the books' narrative, at least one woman has come to rule over one of the major vassal houses in every region of the Seven Kingdoms. Women might not hold political power as often as men do - but they hold it frequently enough that it isn't considered unusual. It is somewhat rare for a daughter to inherit rule directly from her parents, because a lord will usually keep having more children until he has sons - but sometimes couples prove infertile, or only have daughters. It is more common for women to come to political power as widows, serving as regents for their underaged children. Widow-regents should not be simply waved aside, however, as several widow-regents in the narrative have ruled for over a decade and are considered strong political players (i.e. Barbrey Dustin). Logically there are fewer widow-regents when the narrative begins, but so many men die during the course of the War of the Five Kings that several women get widowed and become the new acting heads of their Houses. The North is the most extreme example: so many Northern lords died during the massacre at the Red Wedding that a third of the major Houses in the North are headed by women as of the fifth novel. 
There are nine regions in "the Seven Kingdoms": when the Targaryens conquered and unified them they reformed the contested borderlands between the seven as "the Riverlands", and carved out "the Crownlands" from neighboring kingdoms for the royal dynasty to rule directly. Each of these regions has about a dozen or so major Houses as vassals, such as the Umbers or Karstarks. Each of these major vassals in turn have their own minor vassal Houses, anywhere from a few to a dozen, though they have not been described in as much detail. At least one woman heads a major vassal House in each region during the narrative, and each region currently has around 12 to 15 major vassal Houses (the number has fluctuated across the centuries) - so generally speaking, the ratio of how frequently women hold political power over the major Houses is roughly around one out of every twelve. This may not be an equal ratio (which would be half of all noble houses), but it is far from an insignificant number. 
In the real-life Middle Ages, women actually held land quite frequently in certain areas - though this varied considerably from region to region and century to century. Partially this was because not every region practiced primogeniture but often divided lands (and thus political power) among daughters as well. So many men died so frequently in endemic warfare or crusades that widow-regents were also not uncommon. In some regions of medieval France, the ratio of female handholders to male ones was as high as one out of every eight, sometimes even one out of six (higher than the roughly one out of twelve figure apparent in the Seven Kingdoms). Due to patchy surviving written records not much is known about some sub-regions, however, so there is ongoing debate about how indicative these figures are for medieval Europe as a whole, and just because they were landholders doesn't mean they were the wealthiest landholders (daughters often inherited land, but smaller shares than sons).Aristocratic Women in Medieval France, edited by Theodore Evergates. Philadelphia: University of Philadelphia Press, 1999.Ruth Mazo Karras, Sexuality in Medieval Europe: Doing Unto Others (Routledge, 2005, 2d ed. 2012).
Interestingly, the one out of twelve ratio (sometimes one out of 14 or 15) holds for the all of the "core" regions of the Seven Kingdoms, the wealthy and populous southern kingdoms that all follow the main religion of the Faith of the Seven. The "fringe" regions of the North, Dorne, and the Iron Islands don't have this ratio (the North and Iron Islands have different religions and cultures, while Dorne nominally converted to the Faith of the Seven but nonetheless has a radically different culture). Women come to power much more frequently in Dorne due to its gender-blind inheritance laws. Women also seem to come to power a bit more frequently in the North than the south: it is the only kingdom with a hostile land border and faces wildling attacks from beyond the Wall, and it gets hit hardest by winter, so it presumably has a higher death rate for male lords. This higher death rate in war and winter would mean that widow-regents are more common, or that sons would be exhausted sooner leaving only daughters behind. Indeed, at the time of the Dunk & Egg novellas, House Stark was headed by the "She-wolves of Winterfell" - about five or so widows who were jockeying over who was in charge because five lords of Winterfell died in rapid succession due to various catastrophes (including a major wildling invasion led by a King-Beyond-the-Wall, Ironborn attacks on the west coast, and even a revolt by the savage tribes on Skagos island to the east). Meanwhile, women hardly ever come to rule in the Iron Islands, due to their misogynistic culture. 
Women who hold political power among the major vassal Houses of each region during the narrative of the novels include:
*The North:
**Maege Mormont - ruler of Bear Island, inheriting in her own right after her brother Jeor abdicated to join the Night's Watch, but then Jeor's son Jorah fled into exile in Essos rather than face punishment for selling poachers into slavery. Also a warrior and military commander, due to the strong tradition of warrior-women on Bear Island. Maege had five daughters but no mention of a husband was ever given, or why all of her daughters still have the name "Mormont". Her second daughter Alysane also has two small children, and never told anyone who the father was - sarcastically claiming they were fathered by a bear. Maege's eldest daughter Dacey Mormont was also a warrior-woman and a member of Robb Stark's personal bodyguard, but she was slain at the Red Wedding.
**Barbrey Dustin - Born Barbrey Ryswell, her husband Willam Dustin was killed during Robert's Rebellion. Lady Barbrey has ruled House Dustin ever since as his widow, and is a major political figure in the North, and appears prominently in the narrative of the fifth novel. It is unclear if she has children or has designated an heir. In the TV series, it has been mentioned in passing exactly once by Arya in Season 2 that there is a "Lady Dustin" but her first name wasn't mentioned, and in context the line didn't even make clear that she is the head of House Dustin. 
**Jonelle Cerwyn - inherited rule in her own right after her father and brother were killed in the War of the Five Kings. Her father Medger died of wounds he took at the battle on the Green Fork. Her older brother Cley was then killed at the Sack of Winterfell, when the Northern forces besieging Theon's Ironborn in the castle were surprised and betrayed in their own camp by the Bolton forces led by Ramsay Snow (who then betrayed the Ironborn as well, flaying alive those who surrendered and torturing Theon, while burning the castle and putting many of its household to the sword). Jonelle was thus the head of House Cerwyn as of the beginning of the third novel; she appears in the fifth novel when Northern lords assemble to grudgingly swear fealty to Roose Bolton as the new Warden of the North (at which time she is 32 years old). 
**Lyessa Flint - head of House Flint of Widow's Watch. It isn't clear if she is a widow or inherited in her own right; her son Robin is described as the head of the separate branch of the family, House Flint of Flint's Finger, though the circumstances of how this came about are unknown. Lyessa is mentioned in the second novel, but she does not travel to the harvest feast that Bran holds at Winterfell because she is pregnant. She hasn't been mentioned again.
**Eddara Tallhart - inherited rule in her own right after both her father and brother were killed in the War of the Five Kings. Her father Helman was killed in the Battle of Duskendale - a suicide mission that Roose Bolton sent him on to eliminate loyal Stark supporters who would oppose his betrayal of them. Her brother Benfred was killed when the Ironborn landed on the west coast of the North; they proceeded to seize and occupy House Tallhart's seat at Torrhen's Square (as a feint to lure out Winterfell's defensive garrison), and took the young maid Eddara captive. Despite other losses to the Boltons the Ironborn still hold Torrhen's Square as of the end of the fifth novel, and Eddara remains their prisoner. 
**Donella Hornwood - an elderly woman came to rule as a widow-regent during the novels after her husband Halys Hornwood was killed at the battle on the Green Fork, and their adult son Daryn Hornwood was killed around the same time at the Battle of Whispering Wood. Halys's only remaining potential heir is his bastard son Larence Snow, a 13 year old boy. As the Hornwood succession is tenuous she comes to Winterfell to ask Bran Stark and Maester Luwin for advice and they suggest several options for remarriage, as she is fearful that the Boltons on her northern border cover her lands. On her way back from Winterfell she is attacked and captured by Ramsay Snow, who forcibly married and rapes her. He then flayed the skin off of the elderly woman's fingers, to force her to chew them off to end the pain, then locked her in a tower cell and simply forgot about her, leaving her to starve to death. After the Bolton takeover of the North they apparently claim direct rule over the Hornwoods, though Larence Snow later joins Stannis Baratheon's host in the west. 
*Riverlands:
**Shella Whent - an elderly woman, ruler of Harrenhal at the time of the first novel. She apparently died "off screen" by the time of the fifth novel, after the Lannisters occupied Harrenhal, despoiled her lands, and killed off almost all of her household. The elderly blacksmith Ben Blackthumb says that he worked at Harrenhal for Shella and her father before her, and her grandfather before him, indicating that Shella inherited rule in her own right. Shella dies "off screen" by the time of the fifth novel, during the Lannister occupation, after which the Iron Throne considers House Whent extinct (though in fact Shella's relative Minisa Whent was Catelyn Stark's mother, and thus the Stark children have claim to Harrenhal, but the Lannister's don't acknowledge it). 
*The Vale:
**Anya Waynwood - one of the leading political figures in the Vale, the only female member of the "Lords Declarant" who originally challenged Littlefinger's regency over Sweetrobin Arryn in the novels (though they later came to terms). Given that she is an elderly woman and has adult sons, she probably isn't a regent but inherited rule from her parents. 
***During the Dance of the Dragons, set 170 years before the main novels, the Vale was ruled by Lady Jeyne Arryn, who is explicitly stated to have inherited rule from her parents, not through marriage. 
***At the beginning of the novels, Lysa Tully rules over the Vale as the widow-regent of Lord Jon Arryn, and is expected to rule for many years due to the very young age of their frail son Sweetrobin Arryn. 
*The Crownlands
**Ermesande Hayford - a baby at the time of the second novel, but last living member of her family and thus officially the ruler of Castle Hayford and its lands, inheriting in her own right and not through marriage. 
**Tanda Stokeworth - apparently the widow of Manly Stokeworth, Commander of the City Watch killed in the Sack of King's Landing, meaning that she has been ruling House Stokeworth for the 15 years since the war. She only has two daughters, Falyse and Lollys, both of whom are above the age of majority. Falyse has been married for ten years but is barren. Apparently a widow-regent can sometimes hold onto power longer if she only has daughters. Tyrion meets with her several times throughout the second novel, as without food supplies from the Riverlands or the Reach, half of the trickle of food supplies coming into King's Landing are from Stokeworth and Rosby lands. 
*The Reach:
**Arwyn Oakheart - a widow, but not clearly stated if she inherited in her own right or not. She is said to have several sons, and the youngest is Ser Arys Oakheart, a member of the Kingsguard - meaning that her elder sons must already be grown men, implying that she is not a widow-regent but probably inherited in her own right from her parents. 
*The Westerlands
**Alysanne Lefford - Leo Lefford was the head of House Lefford at the beginning of the novels, but he drowned during the Battle of the Fords (equal to the Battle of the Fords in the TV series), so that by the third novel Alysanne is the new ruler. It is unclear if she is his widow or inherited rule as his daughter or sister.
***In House Lannister itself, Jaime foreswore his inheritance when he joined the Kingsguard, but after Tyrion kills their father Tywin he flees into exile, leaving Cersei as the new head of House Lannister. No one denies that (with Tyrion gone and wanted for patricide) Cersei is her father's heir. 
*The Stormlands
**Mary Mertyns - listed in the appendix of the fifth novel as the head of House Mertyns of Mistwood. She first actually appears in preview chapters for the unpublished sixth novel. She is an elderly but strong-willed woman with sons and grandsons. 
***Brienne of Tarth is not the current ruler of House Tarth because her father is still alive, but all of his other children died in childhood, so Brienne has been treated as his heir-apparent for years. Her father tried to arrange good marriages for her, and this did attract suitors who wanted to gain rule of Tarth through her - but none of them lasted because they all disdained her unfeminine appearance and behavior. Either way, in both the novels and TV series, she isn't really presented as a political figure so much as an independent warrior (she doesn't represent "House Tarth" as a political faction the way Anya Waynwood represents "House Waynwood" and all of its armies). 
*Dorne is exceptional due to its gender-blind inheritance system, so that female rulers are even more frequent there (older daughters inherit ahead of younger sons):
**Larra Blackmont - ruler of House Blackmont, inherited rule in her own right from her parents. Her eldest child and therefore heir under Dornish law is her daughter Jynessa Blackmont. Larra is part of Oberyn Martell's embassy of Dornish lords to King's Landing.
**Nymella Toland - ruler of House Toland in her own right. Her eldest daughter Valena is apparently also her eldest child and heir. Nymella first appears in a preview chapter from the sixth novel, well ahead of the TV storyline as of the end of Season 5.
**Delonne Allyrion - ruler of House Allyrion in her own right. Grandmother of Daemon Sand.
**House Jordayne - the current ruler is a man, but his heir apparent is his daughter and eldest child Myria Jordayne.
**Lady Alyse Ladybright serves as the "lord treasurer" in Sunspear of House Martell. This is an important court position, though it isn't clear if Alyse is head of her House, and otherwise House Ladybright hasn't been significantly mentioned in the novels so it might not be a "major" House. 
There are currently about 15 or so major Houses in Dorne (assuming that House Dalt and House Ladybright can be called "major", though this is unclear). While the other southern kingdoms in Westeros also have around 12 to 15 major vassal Houses each, but on average only have one of those vassal Houses headed by a woman (in peacetime), three times as many major Houses are headed by women in Dorne. For that matter, sometimes the women who come to rule in the other kingdoms do so as widow-regents, gaining power through their husbands (i.e. Alysanne Lefford). In contrast, all of the current female heads of noble houses in Dorne are not widows, but inherited rule in their own right from their parents. Multiple Dornish Houses also have heirs apparent who are older daughters inheriting ahead of younger sons. 
The Iron Islands have a very misogynistic culture, and there is no mention of any woman coming to power there - the Ironborn value strength and have a history of elective kingship, so even on the level of vassal Houses they seem to have a tendency to prefer a more distant relative if he is a strong ruler. Even then, however, during the timeframe of the narrative Yara Greyjoy (Asha in the novels) is a very exceptional female Ironborn warrior, raised as a surrogate son by her father Balon after two of his sons died and the last (Theon) was sent away to be a hostage of the Starks. She captains her own ship and has commanded Ironborn forces in war attacking the North. Balon himself has actually remarked in the novels that he wants his daughter to rule after him; while most Ironborn oppose the idea that she may come to rule, simply because she is a woman, the Drowned Men priests are disconcerted that a surprisingly large minority of vassal Houses are so impressed with her that they are openly in favor of her ruling.
==The social status of women from major vassal Houses - in the TV series==
The TV series has barely presented women heading any of the major vassal Houses at all, even as cameos. Even throwaway dialogue that mentions vassal Houses in passing has changed the gender of the current ruler from female to male - apparently thinking that mention of a woman ruling a major House would require a lengthy explanation out of proportion to the brief lines of dialogue. 
Of the 16 women who at one point or another during the narrative of the novels rule one of the major vassal Houses, not all are prominent characters or even have speaking lines - given that so many male rulers of major Houses were also cut for time (i.e. House Manderly), it is unsurprising and even expected that not all of them would appear even as cameos in the TV series. Such minor characters who are "named" in the novels but don't really enter the narrative, sometimes just appearing in a list in the appendices, include Arwyn Oakheart, Alysanne Lefford, Mary Mertyns, Lyessa Flint, Eddara Tallhart, and Ermesande Hayford (Ermesande is just a baby and her entire subplot with Tyrion's cousin Tyrek was cut for time anyway). In Dorne, Donelle Allyrion and Nymella Toland have similarly only been mentioned in the novels so far (Nymella only appears in a preview chapter from the upcoming sixth novel). Donella Hornwood doesn't exist in the TV series but the entire subplot involving her being captured and killed by Ramsay Snow was also omitted - because Ramsay's introduction was pushed back to Season 3. 
The TV series did mention Shella Whent as the current ruler of Harrenhal in Season 1, when Catelyn calls upon the men at the Crossroads Inn to arrest Tyrion, citing that each of them serve vassals of the Tullys. She isn't mentioned again, though as in the novels she apparently died "off screen" during the Lannister occupation of Harrenhal between Seasons 1 and 2. Barbrey Dustin is a prominent character in the fifth novel and presented as a strong political leader of House Dustin, having conversations with both Roose Bolton and Reek/Theon. The TV series only vaguely referred to her exactly once, in Season 2 when Arya pretends to be a commoner and claims "My mother served Lady Dustin for many years, my lord" - yet even this line doesn't give her first name, or really clearly establish that "Lady Dustin" is in fact the ruler of House Dustin at all. Arya could have just been claiming that her mother was a handmaiden to the wife of the current Lord Dustin. In the cases of both Shella Whent and Barbrey Dustin, however, only sharp-eyed viewers who already read the novels would even pick up on these mentions, each made only once and very briefly, so that TV-first viewers might not have even noticed them as examples of women holding political power. 
Maege Mormont is one of the most prominent female rulers of a major vassal House in the novels: she inherited rule in her own right after her brother and nephew abdicated, she is a warrior-woman in her own right, and one of Robb Stark's major military commanders in battle (not to mention a grandmother). She is also one of only a few of Robb's lieutenants who weren't killed at the Red Wedding, because she was away on a mission to meet with the Crannogmen in the Neck to prepare to retake Moat Cailin. The TV series, however, reduced Maege Mormont to a non-speaking cameo, appearing only in the background of three episodes in late Season 1 when Robb's bannermen assemble. She simply vanishes after that and isn't even in crowd shots from Season 2 onwards. Her fate in the TV series is also a mystery. While book-readers could tell that this was Maege Mormont (as she is an older woman wearing full chainmail) the TV series never gave her speaking lines nor did any other characters ever mention in dialogue that the current head of House Mormont is a woman. Nor has it been prominently explained that Bear Island has a strong tradition of having women-warriors due to constant attacks by wildlings and Ironborn across the seas. TV-first viewers would have no way of knowing that House Mormont is currently ruled by a woman, or that its armies are led into battle by a woman. In both the novels and TV series, much later in the story when Stannis Baratheon arrives at the Wall he sends letters to the Northern lords asking that they acknowledge his rule, but he gets a rejection letter from Lyanna Mormont - one of Maege's younger daughters. In the novels, Jon thinks to himself that Maege has older surviving daughters and wonders why she left Lyanna as acting ruler of Bear Island, and wonders if her sisters let her write the rejection letter to insult Stannis (given that Lyanna is only a ten year old girl). The TV series didn't clearly explain the current status of the Mormont family at all, however: Lyanna Mormont is simply said to be Jeor's niece, that she is "Lady of Bear Island" - but not mentioning what happened to Maege, or if Lyanna is the current or acting ruler of House Mormont. 
Many secondary characters from vassal Houses below the main Great Houses, both men and women, were removed from the TV series simply due to time constraints, so all of the above examples can be attributed to the general wave of condensations made in adapting a lengthy novel series. Nonetheless, by not even mentioning female rulers in minor dialogue, the TV series hasn't presented female rule as the unexceptional phenomenon in Westeros it is in the novels. Yet other changes were made regarding female rulers in the TV series that went above and beyond simple omission from the novels:
While the TV series didn't have time to introduce all of these secondary and tertiary characters, at times - when the head of a House is only mentioned in passing or only makes a cameo appearance - the TV series has changed the gender of the heads of several Houses from female to male, possibly out of fear that audiences would get confused if a woman was presented as a political leader in Westeros, without also providing a lengthy explanation of how she came to that position. In contrast, in the novels there are several female heads of major Houses who have really only been mentioned in passing (essentially as "cameos"), but George R.R. Martin never felt the need to stop the narrative and spend a full page introducing a convoluted explanation of how a woman could, implausibly, come to lead a major House - instead, he typically presented it without explanation, because it happens frequently enough in their society that it isn't worth commenting on. Female rule is not considered very rare and unusual in the books, and thus doesn't really require an explanation: several Houses just happen to be headed by women, either because they inherited it due to having no surviving brothers, or as widows who serve as regents for their children. 
As of the end of Season 5, female rulers have been changed to male ones on four occasions (five if the Martells are counted twice):
*In Season 4 episode 7 "Mockingbird", when Oberyn Martell met with Tyrion in his prison cell, he mentioned in passing that he accompanied his "father" on a trip to Casterly Rock, where he saw the newborn Tyrion. In the novels, it was actually Oberyn's mother who took him on an official visit to Casterly Rock, because she was the ruler of Dorne at the time. She inherited rule in her own right from her parents, ahead of her younger brother Lewyn Martell due to Dornish inheritance law (Lewyn subsequently joined the Kingsguard). Rule later passed to her son and eldest child Doran upon her death. While the name of Doran and Oberyn's mother hasn't been established yet, she was fairly active in the backstory: she was a handmaiden to Queen Rhaella Targaryen (the Mad King's sister-wife) along with Joanna Lannister, where the two became close friends. She was therefore actually traveling from Dorne to Casterly Rock to visit her friend Joanna, whose unborn child was due then, but when they arrived they learned that Joanna had died in childbirth. Why the TV series went out of its way to change a reference from Oberyn's "mother" to his "father" is unknown - but it removed the implication that Oberyn's mother was the previous ruler of Dorne. 
*In the same episode, Season 4's "Mockingbird", Bronn also visited Tyrion in his cell, and discussed how Cersei just bribed off Bronn with a betrothal to the noblewoman Lollys Stokeworth. Tyrion points out that Lollys isn't the heir to House Stokeworth, her older sister Falyse is, and Bronn acknowledges he is aware of that (but hopes to get rid of Falyse soon). In this exchange, Tyrion says that as heir, Falyse will inherit Castle Stokeworth instead of Lollys when their "father" dies. In the novels, the head of House Stokeworth is the widow Tanda Stokeworth, whose husband has been dead for many years. In the novels, Tyrion even meets with her extensively to negotiate food shipments to the capital city. The result was that within the same episode, two separate instances of female political leaders of major noble houses (one of them even a Great House) were changed to be men. The dialogue could have just as easily referred to Oberyn's "mother", and Lollys's "mother" without further explanation, but the scriptwriters went out of their way to change each line to "father". 
*In the Season 4 premiere, "Two Swords", Tyrion greets the embassy of Dornish lords as they arrive at King's Landing, only to find that Oberyn rode ahead of them and is already in the city. In the novels, Oberyn didn't ride ahead but was with the embassy, yet either way Tyrion was expecting his brother Doran and was disconcerted that his more hotheaded younger brother came instead. In the novels, one of the Dornish nobles that accompanies Oberyn is Lady Larra Blackmont, the current ruler of House Blackmont, which she holds through inheritance in her own right. She doesn't have significant dialogue, but it is a visual indication of the different inheritance laws in Dorne that result in women holding political power more frequently. In the TV version, the head of House Blackmont who was in the embassy was genderswapped to be a man instead of a woman, credited as "Lord Blackmont". In fact, this Lord Blackmont is the leader of the Dornish embassy who actually has speaking lines when he talks with Tyrion (and informs him Oberyn isn't there). Thus the TV series could have not only shown a female Dornish ruler as one of the background lords in this scene, but could have made Larra Blackmont the noble who actually has speaking lines with Tyrion. Instead Larra Blackmont was simply omitted and apparently doesn't exist in the TV continuity. Combined with Oberyn's reference seven episodes later in Season 4 to his "father", not his mother, taking him on a visit to Casterly Rock, this removed any hint from the TV series that Dorne practices gender-blind inheritance, unlike the rest of Westeros which practices male-preference inheritance. 
*When Doran Martell was introduced in Season 5, the TV series only showed his son Trystane Martell, and carefully avoided confirming or denying if he has other children - while in the novels, he has three children, and his eldest child and heir is his daughter Arianne Martell. Arianne is actually the POV narrator for many of the Dorne subplot chapters (Jaime never goes to Dorne in the novels). She is also the only female heir to a Great House that was raised from birth knowing she would rule some day (Cersei was behind her brothers in the line of succession, not expected to rule, and thus not trained to rule). Combined with the changed reference to Oberyn's "father" instead of his mother, any mention that Dorne treats women as the legal equals of men and practices gender-blind inheritance was omitted from the TV serie (see more in the "Dorne" subsection below). 
*In Season 5's "High Sparrow", Ramsay Bolton explains to his father that he flayed "Lord Cerwyn" alive because when Ramsay came to collect taxes from him, he defiantly refused to acknowledge Bolton rule, much less pay him. Ramsay goes on to say that he not only flayed Lord Cerwyn but also his wife and brother, while forcing his "son" to watch. Ramsay proudly says that the new Lord Cerwyn paid his taxes as a result. In the novels, Ramsay did kill a Cerwyn, but in different circumstances: Lord Medger Cerwyn died from wounds he took at the battle on the Green Fork, and then Ramsay killed his son Cley Cerwyn during his betrayal of the other Northern forces at the Sack of Winterfell. The new head of House Cerwyn after this was Medger's 32 year old daughter Jonelle Cerwyn, not another son. Jonelle was even later shown in the books among the assembled lords who grudgingly swear fealty to Roose, showing her capacity as the new political leader of House Cerwyn, but Jonelle has simply been omitted entirely from the TV series. No actors were actually present playing Cerwyns in the episode "High Sparrow", these were simply passing descriptions in dialogue that Ramsay gave, so it is unclear why the TV series had a great need to change the reference from a son to a daughter as the new head of House Cerwyn. Possibly the rationale the writers used was that because neither Medger nor Cley were described as dying in the TV continuity the way they did in the novels, Cley is logically still alive. On the other hand, the dialogue never actually gave names for any of these Cerwyns - they are never actually referred to as "Medger" or "Cley" - in which case the TV series isn't really beholden to the family's composition in the novels, and could just as easily have had Ramsay said "I made Lord Cerwyn's daughter Jonelle watch as I flayed him, and now that she's head of House Cerwyn, she paid her taxes."
**Casting reports for Season 6 indicate that a new male "Lord Cerwyn" will appear on-screen, the son of the previous one that Ramsay flayed alive, seeking revenge for his father - outright changing a potential on-screen female political leader from the source material to male. 
Both the mention of Oberyn's "father" and Lollys's "father", however, were subsequently addressed by other material. In the Season 4 Blu-ray set's Histories & Lore animated short for "Robert's Rebellion - Oberyn Martell", Oberyn (in voiceover) indicates that his mother was in fact the previous ruler of Dorne, as she worked hard to secure a match between his sister Elia and Crown Prince Rhaegar Targaryen. Oberyn also outright states in this video that the inheritance system in Dorne is gender-blind and thus there has been a Princess of Dorne as often as a Prince of Dorne. Moreover, when Lollys Stokeworth actually first appeared on screen in Season 5's "The House of Black and White", she directly stated that her mother is the current head of House Stokeworth, not her father. No explanation is given for why Tyrion said her father was still alive back in Season 4's "Mockingbird" (and Bronn didn't correct him at the time), though in-universe this could probably be waved away with the explanation that Tyrion simply misspoke at the time. 
In Season 4, Lady Anya Waynwood actually does appear quite prominently when Sansa and Littlefinger meet with the lords of the Vale, and she is presented as a strong political figure, weighing along with her colleague Lord Royce whether they should commit their armies (which have so far remained neutral) to the War of the Five Kings. Lady Waynwood's appearance in Season 4 was really the only time in the first five seasons of the TV series that a woman appeared on-screen and with actual lines of dialogue as the current head of a major vassal House. Unfortunately, Lady Waynwood has an even more prominent role in the novels, as Sansa (pretending to be Littlefinger's bastard daughter) is preparing to marry her ward Harrold Hardyng, Sweetrobin Arryn's cousin and closest heir, as a step towards taking control of the Vale itself after the sickly Sweetrobin dies. This entire subplot was cut from the TV series, so that Sansa instead marries Ramsay Bolton at Winterfell, who badly mistreats her (Sansa never even met the Boltons in the novels). The result of this major condensation is that Anya Waynwood only appeared in a single episode, 4.8 "The Mountain and the Viper", and did not reappear in Season 5 at all because Sansa was sent off to the Boltons. 
In summary, the presentation of women heading major vassals Houses in the TV series has been:
*The North
**Maege Mormont - a non-speaking cameo appearing in the background in Season 1, who then disappeared without explanation form Season 2 onwards. Never referred to by name.
**"Lady Dustin" - mentionied exactly once and only in passing, not making clear if she is actually the head of House Dustin.
*The Riverlands
**"Lady Whent" - mentioned exactly once and only in passing.
*The Vale
**Anya Waynwood - the only female head of a major vassal House to appear in the TV series with speaking lines. Only appears in one episode in Season 4, though within that episode she does appear quite prominently. 
*The Crownlands
**Lady Stokeworth - Season 4 implied that Tanda Stokeworth had been omitted entirely, as references were changed to Lollys's "father" and not her mother. However, in Season 5 Lollys clearly said that her "mother" is the current head of House Stokeworth (though her first name isn't given). While Tanda physically appeared in the novels' narrative, she has not in the TV series.
*The Reach
**(None)
*The Westerlands
**(None)
*The Stormlands
**(None)
*Iron Islands
**(None - as in the novels)
*Dorne
**(None)
Put another way, in the first five seasons of the TV series there was only one female head of a major vassal House who had speaking lines, another one who briefly appeared in background shots as a non-speaking cameo, and another three who were only mentioned in passing, each exactly once (not even giving their first names), as blink-or-you'll-miss references which TV-first viewers probably wouldn't have even noticed.
In contrast, the following female characters are prostitutes invented for the TV series and not based on the novels: 
*Ros
*Armeca
*Daisy
*Mirelle
*Marei
*Kayla
*Genna
*Mole's Town whore
There are several others, and many prostitute characters do appear in the novels: "Ros" or "Marei" aren't so much invented from scratch as they are a condensation of multiple other prostitute characters from the novels. This list doesn't include prostitutes based on scenes from the novels such as Clea in Braavos or Vala who helps the Sons of the Harpy. 
Still, the number of female prostitutes in the TV series exceeds the number of female rulers of major vassal Houses by a wide margin, and while the TV series has outright removed even the mention of some female rulers by replacing them with male versions (Larra Blackmont, Jonelle Cerwyn, etc.), it has invented quite a few prostitutes - often for use in Sexposition scenes. Most of these prostitute characters had speaking lines (Ros, Armeca, Mirelle, Marei, Kayla, Mole's Town whore - six of them) compared to only one female head of a vassal House who had speaking lines in the TV series (Anya Waynwood). Four of them (Ros, Armeca, Marei, and Kayla) all had speaking lines, did nude scenes, and reappeared in multiple episodes across more than one season, while Anya Waynwood appeared in only a single episode.
==The social status of women beyond the Seven Kingdoms - books vs TV series==
Beyond the Seven Kingdoms, other societies - in Essos, Sothoryos, and Beyond the Wall in Westeros - have not been presented as having women who hold political power as often as they did in the novels. No female magisters are mentioned in the Free Cities or Qarth, nor have any female members been shown of the Iron Bank of Braavos - though there aren't really female magisters who were prominent characters in the novels, so their absence is understandable. In the novels, one of the major informal leaders of the vast slave population in Volantis is an old woman known as the "widow of the waterfront" - she was a former pleasure slave who was married by a Triarch of the city, who owned piers, storehouses, lent money, and sold insurance to ship owners. After her husband died she took over his business assets, and by the time of the novels despite not being an aristocrat she is one of the wealthier people in the city. She enters into Tyrion's storyline when he passes through Volantis, and urges Jorah that if Daenerys comes west the slaves of the city will follow her lead in supporting the Dragon Queen. The widow of the waterfront was cut from the TV series entirely. 
The Dothraki are presented much as they were in the novels: women do not rule, but their priesthood is female. Yet in Slaver's Bay, several of the major aristocratic slaver-families are headed by women. One of the most powerful families in Meereen is the House of Pahl, now stated to be ruled by bitter women after the male heads of the family all died when Daenerys conquered it. The priesthood of Slaver's Bay is also apparently all-female, the Graces, and the high priestess (known as a "Green Grace") of Meereen, Galazza Galare, wields considerable influence within the city. The House of Gelare is also another one of the major aristocratic families in the city. Galazza is therefore a fairly significant character and speaking role in Daenerys's narrative in the books. The TV series heavily condensed the internal political struggles of Meereen that Daenerys faces in Seasons 4 and 5, so no mention is made of any women ruling the major aristocratic families, it has barely been mentioned that they actually have an all-female priesthood ("Graces" have been mentioned but it wasn't made clear that they actually run the temples), and major political figure Galazza Galare has been cut entirely. 
 
Also of minor note in Westeros, while the Vale is in the "Seven Kingdoms", the Hill tribes of the Mountains of the Moon acknowledge the rule of no one. The leader of the Black Ears tribe is a woman, Chella, and she does appear briefly in the TV series (when Tyrion introduces her by name to his father in Season 1), but she had no speaking lines.
The "Free Folk" (wildlings) that live beyond the Wall actually have a strong tradition of having women warriors, and several of their clans in the novels are headed by women. The vanguard of Mance Rayder's army is even commanded by the cruel Harma Dogshead, so-called because as a war-banner she uses a totem with a dog's head impaled on it (killing a new dog every fortnight to supply a new head). Harma is killed in the Battle of Castle Black by Stannis's forces. Another wildling chieftainess is Morna White Mask, so-called because she wears a mask made of white weirwood and never takes it off. After Mance's defeat, Morna is one of the wildling leaders that swears fealty and good behavior to Jon Snow in exchange for her and her followers to be allowed to pass to the south side of the Wall. In the novels, Mance Rayder has a wife named Dalla who dies in childbirth during the Battle of Castle Black itself, though she is survived by her sister Val. Following Mance's defeat and execution, his sister-in-law Val becomes a sort of informal leader/spokesperson for many of the wildlings who followed him. Men in the Seven Kingdoms, from both Stannis's army and the Boltons, are impressed with Val's capability and call her the "wildling princess" - though Val herself points out she has no formal position, she's just Mance's sister-in-law. 
The TV series has barely presented any women as leaders among the wildlings. Mance's sister-in-law Val, a major speaking role in the novels, was cut entirely. Harma Dogshead, one of Mance's main lieutenants, was also cut entirely. Ygritte does appear as a major character in the TV series but she's just an individual warrior - not presented as a "leader" of the wildlings at all, commanding other warriors. The one female wildling leader to appear in the TV series was the invented character Karsi in Season 5's "Hardhome" - who could loosely be seen as the TV-version of Morna White Mask, given that like Morna she accepts Jon's terms to head south of the Wall (though she then gets killed in the same episode). Even Karsi, however, was not really intended by the producers to be an example of a capable female leader exercising political power: the part was originally written as a man. 
Speaking in an interview with The New York Times, actress Birgitte Hjort Sørensen (Karsi) responded to a comment about how "maternal" Karsi was to her children, by saying how delighted she was that her character wasn't written in a patronizing way or downplayed as a leader because she was female:
:"You say 'maternal' and certainly she was in that moment. But I was quite pleasantly surprised that this was a role where gender really didn’t matter. I didn’t feel I was 'the woman chieftain.' I felt like we were all on the same team together. That was a fun experience for me because it’s rare."
As it turns out, however, director Miguel Sapochnik explained in a separate interview with MTV.com that the reason for this is that Karsi was originally written to be a man, and only recast with a female actress late in production:
:"She was a guy originally, and then somewhere in the process we thought it might be cool if she were a mother, and show her sending off her own kids to make that moment with the corpse children really resonate emotionally. As the sequence was refined, she emerged as this clear representative of all the wildlings, which was organic, and it made us care. Then we started casting and saw Birgitte’s work and she got the part."
In the novels, one of Tormund's sons died and was later raised as a wight, and he actually killed the wight himself. Regardless of being a man, Tormund was still distraught about it as a father:
:"Had to see to him m’self. That was hard, Jon." Tears shone in his eyes. "He wasn't much of a man, truth be told, but he'd been me little boy once, and I loved him." (A Storm of Swords, Jon X)
Thus Karsi is only presented as co-equal to all of the other wildling leaders because the part was written as a man, and wasn't changed to be a woman to establish a more equal gender ratio among their leaders, but to play into the stereotype that women are more "nurturing" than men are towards children (a plot point actually taken away from Tormund, a father, in the novels).
==Major female characters from the Great Houses - books vs TV series==
Apart from the general absence of many secondary characters due to time constraints, the women from the Great Houses that actually appear in the TV series have been presented with variable status compared to the novels: 
===Women from Great Houses whose political prominence has decreased in the TV series===
Catelyn Stark's role as a political leader of the Stark faction was drastically reduced in the TV series, with most of her political agency given to her son Robb Stark instead. Catelyn's role was drastically reduced to purely the motherhood aspects of the character, often heard worrying about her babies (apparently to make her more sympathetic) instead of showing political leadership. In the novels, Catelyn and Robb essentially run the Stark faction as a team: he is an expert military leader, but his mother is his primary advisor on political matters - she grew up in southern Westeros and is more familiar with its complex court politics. 
Most of this was removed from the TV series: in the novels it is Catelyn and not Eddard that wants him to go to King's Landing to find out who killed Jon Arryn - the TV series changed this so that she weeps as he chooses to leave. In the second novel Catelyn's POV narration says that she wishes she could be back at Winterfell with her younger children, but she knows there's a war going on and she is needed at Riverrun managing their faction's political affairs. The TV series changed this to have Catelyn actively planning to return to Winterfell and talking about how much she misses her children, instead of discussing political strategies. The TV series also invented a monologue during Season 3 in which she blames herself for wishing that Jon Snow would have died when he had a bad fever as a child - and that all of their family's bad fortunes are somehow the gods punishing her for this (though something like this could have happened in the novels, and Catelyn does have a habit of of blaming herself for things that can't really be her fault). 
It is possible that all of these changes were made in an attempt to make Catelyn more sympathetic to the audience despite the fact that she hates Jon Snow, i.e. not showing her as a stern and firm political leader and emphasizing her "maternal" aspects. The novels, however, make it a point that it is entirely normal and expected for Catelyn to dislike Jon Snow, and even Jon knows this. He is a bastard child that her husband made the shocking move of taking to his home castle to raise alongside her own children. In their society, Ned's choice to do this deeply shamed his lawful wife - specifically, Catelyn, Ned, and Jon all know that this is something shameful that Ned did to Catelyn. Nor does Catelyn mistreat Jon - she is simply cold to him and tries to ignore him, and Jon himself doesn't think this is unusual or expect Catelyn to behave otherwise. She is not his stepmother. Another possibility is that the TV series wanted to increase Robb Stark's role and felt that having his own mother be his main political advisor would diminish his importance. 
Catelyn's decision to free Jaime Lannister to trade him for her daughters' freedom was presented as somewhat rash in the novels, but at least understandable: Joffrey is a sociopathic monster and he might one day just kill Sansa on a whim as he did her father, even if it would be politically disastrous to do so. It is considered a terrible exchange, freeing one of the Lannister's major warriors and military commanders in exchange for a young girl, but Catelyn's actions aren't presented as without merit. 
At the same time, the TV series drastically changed Robb Stark's character to almost lionize him as an ideal leader, when a major point about Robb Stark in the novels is that he is a deconstruction of the idealized warrior boy-king, and is in fact a flawed political leader. Robb is indeed a great military leader, but not unlike his father or his namesake Robert Baratheon, he is a terrible politician. All of the political failures that befall the Stark faction, ultimately resulting in their defeat, are actually the result of decisions Robb made: sending Theon to try to get the Greyjoys on their side, blaming his uncle Edmure Tully for not anticipating his war strategy at the Battle of the Fords when he should have just told him what it was in the first place, and executing Rickard Karstark for killing Lannister prisoners even though it lost him the support of the Karstark armies. The TV series does show Catelyn objecting to these examples somewhat, but Robb's largest blunder was when he chose to marry a political nobody, ruining his promised marriage-alliance with House Frey - whose forces abandon him, and later betray him to his death. The TV series didn't really stress that Robb was making bad political decisions which were ultimately his own fault. Robb's marriage subplot was so drastically changed in the TV series that George R.R. Martin asked the scriptwriters to change the name of his wife from Jeyne Westerling (as in the novels) to "Talisa Maegyr", to reflect the fact that it wasn't remotely similar to what he wrote. In the novels, when Jaime hears that Robb broke his marriage-pact with the Freys, he instantly remarks that Robb just lost the war (nor does he say this unsympathetically, but stunned at how Robb could do something so rash). The TV series presented Robb marrying Talisa as somehow heroically following his heart (as they described Season 2 as "the season of romance" in the commentary); Catelyn is presented as wrong for warning him about his political obligations, and Walder Frey is presented as unfairly blaming Robb, even though he in fact went back on his word. In the novels, Robb at least had the sense to leave Jeyne Westerling back at Riverrun when he went to the Twins, rather than offend Lord Frey with her presence - in the TV series Talisa simply accompanies Robb to the Twins, with no thought that this might be politically offensive (nor is it apparently presented as such by the writers).
The end result was that most of Catelyn's position as a strong political figure for the Stark faction in the novels was largely erased from the TV series, instead giving most political decisions to Robb - possibly because the TV series did not want to depict Robb as being somehow dominated by his mother, even though they are very much a team in the books. 
As Sue the Fury, a fansite columnist from WatchersOnTheWall.com put it:
:"Whatever Happened To Catelyn Tully? - The issue with her that we've encountered, slightly in Season 1 and more noticeably in Season 2, is that we're only seeing one aspect of her character: her motherhood...All motivations, actions and value are directly connected to Catelyn’s role as mother to her children, her possible failures in that role, and her desire to be reunited with the kids. While dedicated parenthood is an admirable trait, in Cat's case we have seen all other aspects of her character erased. The simple archetype of the strong mother may be powerful, but frankly, it’s not that interesting to watch or particularly relatable. I'm saying that as a mother myself. We are more than our love of our offspring, and George R.R. Martin's Catelyn was more complex than a woman who desires nothing but to be at home with her little ones. She adores her children and acts in their interest but she is politically astute. She doesn't necessarily think that she has to be by their side all the time in order to be doing what is best for them. The problem with TV-Catelyn is that archetypes only make for interesting drama when they're being deconstructed, and that isn't happening...The show insists that Catelyn's children be her entire world by phasing out her political agency...What is the point of these changes? Alterations to make the story flow are expected, and sometimes welcomed; the POV chapter structure of ASOIAF would make a direct translation jarring and disconnected onscreen. However, we're seeing some arbitrary character changes that take away what we loved about the story to begin with."Adaptation and the Women of Ice and Fire
===Women from Great Houses whose political prominence has not changed in the TV series===
Aside from the Starks, the status of women in several other Great Houses is generally similar to what it was in the novels. 
Daenerys Targaryen's status as a political figure has not drastically changed between the novels and TV series, and she does become Queen of Meereen. Daenerys does not achieve this within a typical political framework, through inheritance, marriage, etc., but through conquest, with baby dragons and an army of freed slave-soldiers. Therefore while Daenerys is shown as holding political power in both the books and TV series, her activities do not reflect "societal patterns", and are quite exceptional. 
Lysa Arryn rules over the Vale as Jon Arryn's widow, even though she has become mentally unhinged. She rules as a widow-regent for their sickly young son Sweetrobin Arryn, until she is killed by Littlefinger (in Season 4 of the TV series). She is treated as a major political figure but refuses to join either side in the War of the Five Kings and keeps her armies neutral: no one realizes that this was part of Littlefinger's plot, to trick the Starks and Lannisters into fighting each other to exhaust their strength, while Lysa would put the Vale's full-strength armies at his disposal. Ultimately Lysa is mentally unstable, but this closely matches what happened in the novels. 
Among the Lannisters, Tywin's wife Joanna is actually said to have almost co-ruled with him but she has been dead for decades by the time the narrative takes place. Among either the Lannisters or Baratheons, the only particularly active female leader is Queen Cersei herself. In both books and TV series, Stannis's wife Selyse isn't politically active but is primarily a religious fanatic, following Stannis's advisor Melisandre (who also only wields political power in the sense that she influences Stannis). 
Cersei Lannister is a major character in the TV adaptation, and is presented as a major figure in the Lannister faction as she was in the novels, though several features were moved around or omitted for time. In the novels it is Cersei, not Joffrey, who explicitly orders the death of her husband Robert's bastard Barra (and it is mentioned she has had others killed). This was in part her revenge on Robert shaming her in this way but also a very practical concern that some would consider the bastards (i.e. Gendry) to have a better claim to the throne. After Tywin returns to King's Landing Cersei is politically sidelined for the most part, and after Tywin dies she turns out to be very inept at rule - but this is essentially what happened in the novels. Several other changes were made to Cersei's characterization, apparently to try to match the warped mix of sympathy and disgust she can illicit from readers in the novels: the TV series invented the detail in Season 1 that she actually did have a trueborn son with Robert but it died in the cradle. Various other minor points were tweaked with Cersei's characterization throughout the TV series, but these did not affect the portrayal of the level of political power that she wields. On a societal level, Cersei as a woman has the right to rule through her underage son as Queen Regent - it's just that Cersei personally isn't a very good ruler, even compared to other women in the narrative.
One major Lannister woman who was cut from the TV series was Tywin's younger sister Genna Lannister, who married a younger Frey son. As a result she doesn't have any formal rights to rule given that her meek husband is still alive, though she is still both strong-willed and respected. Jaime meets with her when he goes to check in on the Freys besieging Riverrun after the Red Wedding. 
Otherwise, neither House Bolton nor House Frey had any women holding political power in the novels. Walder Frey treats each new wife like breeding stock and no Frey women hold positions of power, while Roose Bolton's first two wives died some years ago. Roose married Fat Walda Frey to cement their alliance after the Red Wedding - which occurs in the TV series as well. Walda had a few more lines in the novels; she is presented as actually fairly intelligent, but otherwise in both versions she doesn't wield any political power. 
The House Greyjoy storylines have been drastically cut in the TV series, to the point that they barely appeared after Season 2 ended other than brief cameos, and didn't appear in Season 5 at all. In the novels women actually rarely if ever come to political influence in Ironborn society, even compared to the mainland. Balon Greyjoy's wife Alannys is still alive but she went half-mad with grief after losing all of her sons at the end of the Greyjoy Rebellion (with Theon taken away), and returned to her home castle at Harlaw to live in her dotage. 
Yara Greyjoy (named Asha Greyjoy in the novels), however, is quite an exceptional Ironborn woman, a warrior in her own right who has risen to captain her own ship and command soldiers in battle. Generally her portrayal in Season 2 was similar to the novels, in that she is a warrior and that Balon trusts her with leading his main attack against the North (at Deepwood Motte). Asha Greyjoy is even a POV narrator in the novels, and after Theon is presumed dead she is vying with her uncles to be named her father's heir and rule as Queen of the Iron Islands some day. Essentially all of the Greyjoy subplot was cut from the TV series after Season 2, however, the result being that it removed one of the few women in the novels who is a military and political leader (even Brienne of Tarth is unusual for being a woman with military skill, but she isn't a commander or political figure). On the other hand, when Yara did appear in Season 2 she was portrayed similarly to the novels, as a strong and respected military commander - and reports now confirm that the major subplot in which Yara fights for political power among the Ironborn will not ultimately be omitted, but was pushed back to Season 6.
===Women from Great Houses whose political prominence has increased in the TV series===
House Tyrell has women in very prominent albeit informal and unofficial political roles. Olenna Tyrell is in many ways the real leader of the Tyrell faction, closely associated with her granddaughter Margaery Tyrell. 
If anything, because the Tyrells were not POV characters in the novels, the TV series has actually presented them more prominently. The novels don't have any scenes of Olenna and Margaery in private discussing their political strategies (scenes that pass the Bechdel Test), but the TV series took time to invent and portray such scenes (something similar probably happened in the novels, but "off screen").
Margaery is presented as intelligent in the novels but the TV series more clearly makes her a behind-the-scenes political player at the royal court. The showrunners have also openly described Olenna as essentially the female equal but antithesis of Tywin Lannister - she is just as intelligent and cunning as Tywin, but while he rules through fear she tries to rule by manipulating people with real favors. 
On the other hand, however, both Olenna and Margaery don't officially hold any political powers. Neither of them ever inherited rule in their own right from their parents, and neither of them was ever a widow-regent for an underaged child. Politics in Westeros is heavily based on the family dynamics and marriage-alliances between rival aristocratic dynasties, and in these matters Olenna has a great sphere of influence, but fundamentally, she wields power by manipulating or advising her son. Margaery wields power by manipulating her three different husbands. Neither of them holds any official "office" or rules in their own right, the way that Maege Mormont or Arianne Martell did in the novels.
Still, the TV series has greatly increased the visibility of Olenna and Margaery Tyrell compared to the novels, in which their activities were implied or described by other characters, but largely "off screen". Both of them are presented as major players in the political landscape of the Seven Kingdoms.
===Dorne and House Martell===
 
While female rulers are actually more common in Dorne in the novels, the TV series itself has never mentioned women holding political power in Dorne at all, nor that women are legally equal to men under Dornish law, and that therefore unlike the rest of the Seven Kingdoms the Dornish practice gender-blind inheritance. Only one of the Histories & Lore animated bonus videos in the Season 4 Blu-ray set mentioned that Dorne follows gender-blind inheritance, and that the previous head of House Martell and ruler of Dorne was Doran's mother - a point easily overlooked by viewers that only watch the live-action TV episodes and don't follow the bonus materials.
For that matter, showrunners David Benioff and D.B. Weiss - who specifically wrote both "Two Swords" and "Mockingbird" and decided not to include Arianne Martell in the series - don't actually write or oversee the Histories & Lore video bonus materials. Bryan Cogman started writing them in Season 1, and afterwards (including for Season 4) they were written by Dave Hill, though Cogman still oversees and reviews his finished work. Therefore there might have been a miscommunication between Benioff and Weiss on one hand, removing references to female rulers and not including any mention of Dorne's equal inheritance law from the main series, and on the other hand Cogman and Hill, who included mention of Dorne's equal inheritance law in the animated bonus videos. It isn't clear if Cogman and Hill were simply working based on the novels and weren't aware that Benioff and Weiss enacted a pattern of not mentioning Dorne's equal inheritance laws in the main TV series, or if they were aware that Benioff and Weiss were removing mention of it, but basically sneaked mention of it into the wider "TV continuity" by including it in bonus materials. Still, viewers who only watch the main live-action TV series and don't pay attention to the bonus features such as the animated featurettes would still, as of the end of Season 5, be totally unaware that the legal status of women is different in Dorne. 
When Doran Martell was introduced in Season 5, only his son Trystane Martell was introduced (given that his betrothal to Myrcella Baratheon is a plot point), while avoiding any mention of his older two children from the novels: his son Quentyn, and his eldest child and heir, his daughter Arianne Martell. In the novels, Arianne is the only woman who is the heir-apparent to one of the Great Houses, and in fact been raised from birth expecting to lead a Great House (Cersei was never expected to lead House Lannister because she had two brothers ahead of her in the line of succession). Arianne is the POV narrator for many of the chapters in the Dorne subplot - and indeed, she was the only "woman of color" POV narrator to appear in all of the first five novels (in fact, she was the only non-white POV narrator, male or female). 
On the other hand, the TV series never clearly stated that Trystane was Doran's only son - indeed, back in Season 2 when Myrcella's marriage proposal was first introduced, Tyrion said that he was arranging a marriage-alliance with House Martell, between Myrcella and their "youngest son" - implying that Doran has other children."I'm brokering an alliance with House Martell of Dorne. Princess Myrcella will wed their youngest son when she comes of age." -- Tyrion, Season 3 episode 3, "What Is Dead May Never Die" This is a tactic the TV series has used before, when the producers aren't sure if a character can ever appear due to time constraints but they are reluctant to officially give up on ever including them in later seasons: in Season 2, dialogue was carefully phrased to say that Stannis Baratheon has "no sons" to leave the option open to later include his daughter Shireen, and in fact they later were able to introduce her in Season 3. 
Nonetheless, as of the end of Season 5, Arianne Martell has been omitted from the TV continuity and may never appear at all. Her absence, combined with referring to Oberyn's "father" instead of his mother in "Mockingbird", and genderswapping the head of House Blackmont to be a man instead of a woman, removed any indication that Dorne practices gender-blind inheritance in the live-action episodes of the TV continuity.
==TV continuity versus the novels' continuity==
In summary, when it comes to presenting the social status of women in the TV series:
*While the novels have about 16 women who currently head major vassal Houses, the TV series has only presented one with speaking lines, Anya Waynwood, who only appeared in one episode. Three or four other female leaders were only blink-or-you'll miss cameos (either non-speaking or only mentioned).
*On four separate occasions (five if you count removing Arianne Martell), the TV series has actually replaced female heads of major Houses with men. They were not simply omitted due to time constraints, but replaced with male characters - particularly in the case of Larra Blackmont, whose male counterpart in the TV series has speaking lines.
*The TV series has never established on-air one of the defining features of Dorne: that women are equal to men under Dornish law, and that the Dornish practice gender-blind inheritance. Only one of the bonus videos mentioned this, but it might have been due to miscommunication among the writers, given that it wasn't mentioned on-air when the Dornish appear in Season 4 or Season 5.
*The TV series has outright omitted Arianne Martell, Doran's daughter and eldest child, and thus raised as his heir apparent under Dornish law - again giving no hint that women inherit political power as often as men do in Dorne. 
*Catelyn Stark's role as the practical co-leader of the Stark faction was largely removed to focus on her motherhood aspect, transferring most of her political agency to her son Robb.
*Yara Greyjoy was presented as a capable military leader in Season 2, only to then practically disappear for three seasons (and not appear in Season 5 at all). Even then she is considered in-universe to be unusual in Ironborn culture.
*The two women from Great Houses that actually do hold political power in the TV series, Lysa Arryn and Cersei Lannister, only possess it through men as widow-regents - and both are presented as mentally unstable and generally unfit to rule. When Cersei does inherit rule of House Lannister upon her father's death, she nearly destroys her faction through incompetence (though this happened in the novels, other positive female leaders were removed). 
*Daenerys Targaryen is shown to be a capable and powerful political leader, but she is not presented as part of any one social system, but an unusual aberration - as if a powerful female leader is as rare and miraculous as the return of dragons (or indeed, required dragons to come about). 
*The House Tyrell women, Olenna and Margaery, have much greater on-screen presence in the TV series than the novels. However, they do not officially "hold" political power at all, not even as widow-regents - only through how they are able to manipulate the men around them. 
*Only one wildling leader was presented as a woman, Karsi - but the character was written as a man, and changed to a woman at the last minute to play to the stereotype that women are inherently more "nurturing" to children than men. 
As TV writer Bryan Cogman pointed out, the TV series is an alternate continuity from the A Song of Ice and Fire novels' continuity, and certain things are simply different between them:
:"If you read comics, if you read DC comics, there's Earth 1, there’s Earth 2, and the way I reconcile it, as a fan of the books — as one of the biggest fans of the books — there's Westeros 1 and Westeros 2, and they’re alternate universes; some things are the same, some things are different."
Executive producers David Benioff and D.B. Weiss have repeatedly said that the TV continuity is meant to stand on its own and not be compared to the novels. 
According to this principle, the alternate "Westeros 2" that is described in the TV continuity is simply, and officially, a world in which women have a significantly lower social status than in the novels, and in which women hold political power much more rarely.
==Behind the scenes==
As of the end of Season 5, only one female staff writer has ever worked on the TV series: Vanessa Taylor. She worked on the series in Seasons 3 and 4, but then left to head other film projects. Jane Espenson also wrote one episode in Season 1, but she wasn't a staff writer (that is, actively a member of the roundtable meetings at which the other 3-4 writers discuss adaptation decisions). Seasons 4 and 5 therefore had no female scriptwriters whatsoever. 
While not as specifically involved with storyverse decisions and points of dialogue, only one female director has ever worked for the TV series, Michelle MacLaren. She worked on the series in Seasons 3 and 4, but also left for other film projects afterwards. There were no female directors in Seasons 1, 2, or 5. Season 5 therefore marked the first time that there were no female scriptwriters or directors working on the TV series. The list of directors for Season 6 has also been released and does not include any women.
==References==
Status of women