Hakīm Sa'd-al-Dīn ibn Shams-al-Dīn Nizārī Bīrjandī Quhistānī (Persian: حکیم سعدالدین بن شمس‌الدین نزاری بیرجندی قهستانی‎ ‎ ), or simply Nizari Quhistani (died 1320 CE), was a 13th-century Ismaili author and poet, who lived in the time of the Imam Shams al-Din Muhammad.
 Nizari was born into a family of landed gentry approximately a decade after the capitulation of the Alamut state and hailed from the town of Birjand.
 Nizari is the only Ismaili poet of this period whose works are extant.
The landed gentry and nobility of Devonshire, like the rest of the English and European gentry, bore heraldic arms from the start of the age of heraldry "circa" 1200-1215.
 The fashion for the display of heraldry ceased about the end of the Victorian era (1901) by which time most of the ancient armigerous families of Devonshire had died out, moved away or parted with their landed estates.
 In 2015 a very few ancient families remain in the county represented by direct male descendants, most notably Courtenay of Powderham, Fulford of Fulford, Kelly of Kelly, Cruwys of Cruwys Morchard, Clifford of Chudleigh, Acland of Killerton and Broadclyst, Wrey of Tawstock, etc.
 A few ancient Devon estates are still owned by descendants via female lines, for example Castle Hill, Filleigh, Molland, Incledon, Braunton, Hall, Bishop's Tawton, Newnham Park, etc.
 In most cases the laws of English heraldry preclude the transmission of paternal armorials via a female heiress (other than in the form of quartering), thus most of these inheritors via female lines, generally deriving from the same pool of high-status English armigerous families, bring their own paternal heraldry, possibly previously foreign to Devon, to the estates inherited.
 For example, the Irish arms of Gore (Earl of Arran) are now associated with Castle Hill, Filleigh, until 1958 the seat of the last male representative of the Fortescue family which originated in Devon in the 12th century.
 In a few cases however, male heirs via female lines have been required by the legator to seek royal licence to adopt his own arms and surname, otherwise destined to disappearance, in lieu of the legatees own.
 This was the case with the families most notably of Rolle, Basset, Stucley, Walrond, etc.
Marie-Madeleine Pioche de La Vergne, comtesse de La Fayette (baptized 18 March 1634 – 25 May 1693), better known as Madame de La Fayette, was a French writer, the author of "La Princesse de Clèves", France's first historical novel and one of the earliest novels in literature.
Jane Austen ( ; 16 December 1775 – 18 July 1817) was an English novelist known primarily for her six major novels, which interpret, critique and comment upon the British landed gentry at the end of the 18th century.
 Austen's plots often explore the dependence of women on marriage in the pursuit of favourable social standing and economic security.
 Her works critique the novels of sensibility of the second half of the 18th century and are part of the transition to 19th-century literary realism.
Adrienne Catherine de Noailles, comtesse de Tessé (] ; 24 December 1741 – December 1813), was a French salon holder and letter writer.
 She was daughter of Louis, 4th duc de Noailles, sister of the 5th duc de Noailles and aunt of Marie Adrienne Françoise de Noailles, held a salon and corresponded with Thomas Jefferson in the early 19th century.
Eliza, Comtesse de Feuillide (née Hancock; 22 December 1761 – 25 April 1813) was the cousin, and later sister-in-law, of novelist Jane Austen.
 She is believed to have been inspirational for a number of Austen's works, such as "Love and ", "Henry and Eliza", Lady Susan and Mansfield Park.
 She may have also been the model from whom the character of Mary Crawford is derived.
Polish landed gentry (Polish: "ziemiaństwo, ziemianie" , from "ziemia", "land") was a social group or class of hereditary landowners who held manorial estates.
 Historically, "ziemianie" consisted of hereditary nobles ("szlachta") and landed commoners.
 The Statutes of Piotrków (1496) restricted the right to hold manorial lordships to hereditary nobility.
 The non-nobles thus had to either sell their estates to the lords or seek a formal ennoblement for themselves (not an easy task), or had their property taken away.
 A rare exception was the burgesses of certain specially privileged "ennobled" royal cities who were titled "nobilis" and were allowed to buy and inherit manorial estates and exercise their privileges (such as jurisdiction over their subjects) and monopolies (over distilleries, hunting grounds, etc.).
 Therefore, in the "szlachta"-dominated Polish–Lithuanian Commonwealth there was almost no landed-gentry in the English meaning of the term, i.e. commoners who owned landed estates.
 With the Partitions these restrictions were loosened and finally any commoner could buy or inherit land.
 This made the 20th century Polish landed gentry consist mostly of hereditary nobles, but also of others.
Beatrice Inez Lisette (Paget) Holden (21 November 1903- 30 May 1974) was a British writer and Bohemian social figure and journalist, also known for her association with George Orwell.
 Born at Wellesbourne, Warwickshire to Wilfred Millington Holden (of the family listed in Burke's Landed Gentry 1952 edition as 'Holden of Bromson', a branch of the family of 'Holden of Hawton and Sibdon'; he served as a Lieutenant in the Bihar Light Horse and 15th Hussars) and Beatrice Mary Byng Paget (the daughter of Herbert Byng Paget, of Darley House, Darley Dale, Derbyshire, of the family listed in Burke's Landed Gentry as 'Paget of Loughborough'), with an elder brother, Wilfred Herbert, born in 1902, she was a cousin of the twins Celia Mary and Mamaine, who became Arthur Koestler's second wife.
 Her first memory was her father shooting at- and missing- her mother; their relationship was a fraught one, as was Holden's own relationship with her mother, who was considered to be the second best horsewoman in England.
 She kept fifteen chargers, but although her extravagant nature allowed her to visit the Ritz when in London, her daughter did not benefit from it.
 According to Bluemel (in 'George Orwell and the Radical Eccentrics', which devotes considerable attention to Holden), Holden's status as 'a dropout from the gentry class who worked as both factory hand and intellectual' is a contributing factor in the value of her work both generally speaking and for feminist scholars.
Robin Aubert (born May 13, 1972 in Ham-Nord, Quebec) is a Canadian actor, screenwriter and film director.
 He is most noted for his performance in the film "The Countess of Baton Rouge (La Comtesse de Bâton Rouge)", for which he received a Genie Award nomination for Best Actor at the 18th Genie Awards in 1997, and his 2017 film "Ravenous (Les Affamés)", which won the Toronto International Film Festival Award for Best Canadian Film at the 2017 Toronto International Film Festival.
A.M.W. Stirling (26 August 1865, London – 11 August 1965) was the author of several books dealing mostly with the lives and reminiscences of the British landed gentry of Yorkshire.
 She was also the founder of the De Morgan Centre for the Study of 19th Century Art and Society.

Question: What female author whose works are known to interpret, critique and comment upon the British landed gentry at the end of the 18th century is related to Eliza, Comtesse de Feuillide?
Answer: Jane Austen