Question: In what century did the land surrounding the Grand Duchy of Lithuania come to existence?

Context paragraphs:
Lithuanian Crusade: The Lithuanian Crusade was a series of campaigns by the Teutonic Order and the Livonian Order, two crusading military orders, to convert the pagan Grand Duchy of Lithuania into Roman Catholicism.  The Livonian Order settled in Riga in 1202 and the Teutonic Order arrived to Culmerland in 1230s.  They first conquered other neighboring Baltic tribes – Curonians, Semigallians, Latgalians, Selonians, Old Prussians (see Livonian Crusade and Prussian Crusade).  The first raid against the Lithuanians and Samogitians was in 1208 and the Orders played a key role in Lithuanian politics, but they were not a direct and immediate threat until 1280s.  By that time the Grand Duchy of Lithuania was already an established state and could offer organized defense.  Thus for the next hundred years the Knights organized annual destructive "reise" (raids) into the Samogitian and Lithuanian lands but without great success: border regions in Samogitia and Suvalkija became sparsely inhabited wilderness, but the Order gained very little territory.  The Grand Duchy finally converted to Christianity in 1386, when Grand Duke Jogaila accepted baptism from Poland before his wedding to reigning Queen Jadwiga and coronation as King of Poland.  However, the baptism did not stop the crusade as the Order publicly challenged sincerity of the conversion at the Papal court.  Lithuania, together with its new powerful ally Poland, defeated the Order in the decisive Battle of Grunwald in 1410, which is often cited as the end of the Lithuanian Crusade.  The final peace was reached by the Treaty of Melno (1422).

Palemonids: The Palemonids were a legendary dynasty of Grand Dukes of the Grand Duchy of Lithuania.  The legend was born in the 15th or 16th century as proof that Lithuanians and the Grand Duchy are of Roman origins.  Already Jan Długosz (1415–1480) wrote that the Lithuanians were of Roman origin, but did not provide any proof.  The legend is first recorded in the second edition of the Lithuanian Chronicle produced in the 1530s.  At the time the Grand Duchy of Lithuania was quarrelling with the Kingdom of Poland, rejecting the claims that Poland had civilized the pagan and barbaric Lithuania.  The Lithuanian nobility felt a need for the ruling dynasty to show upstanding origins, as the only available chronicles at the time were written by the Teutonic Knights, a long-standing enemy, and depicted Gediminas as a hostler of Vytenis.

Lithuanian Chronicles: The Lithuanian Chronicles (Lithuanian: "Lietuvos metraščiai" ), or Belarusian-Lithuanian Chronicles (Belarusian: Беларуска-літоўскія летапісы ; Russian: Белорусско-литовские летописи ) are three redactions of chronicles compiled in the Grand Duchy of Lithuania.  All redactions were written in the Ruthenian language and served the needs of Lithuanian patriotism.  The first edition, compiled in the 1420s, glorified Vytautas the Great and supported his side in power struggles.  The second redaction, prepared in the first half of the 16th century, started the myth of Lithuanian Roman origin: it gave a fanciful genealogy of Palemon, a noble from the Roman Empire who founded the Grand Duchy.  This noble origin of Lithuanians was important in cultural rivalry with the Kingdom of Poland.  The third redaction, known only from the Bychowiec Chronicle, elaborated even further on the legend, but also provided some useful information about the second half of the 15th century.  The three redactions, the first known historical accounts produced within the Grand Duchy, gave rise to the historiography of Lithuania.  All medieval historians used these accounts, that survived in 22 known transcriptions, as basis for their publications and some of the myths created in the chronicles persisted even to the beginning of the 20th century.

Nalšia: Nalšia or Nalšėnai (sometimes Nalsen, Nalse) was an ancient land (regional duchy, a subject of Polatsk) in the early stages of the Grand Duchy of Lithuania.  It is mentioned in written sources from 1229 to 1298.  The references to it cease as it was fully incorporated into the Grand Duchy.  While it is known that it was on the north-eastern border of Lithuania proper, the exact location is unknown and is debated among historians.  It is believed that Nalšia was between Livonia and the Duchy of Lithuania and bordered Deltuva.  Towns of Švenčionys and Utena are often identified as the most prominent settlements in the land.  Several dukes of Nalšia are known.  The most prominent of them was Daumantas of Pskov.  Others were Lengvenis, nephew of Mindaugas, Suksė (Suxe), who defected to the Teutonic Knights, and Gerdenis, rival to Daumantas.

Muscovite–Lithuanian Wars: The Muscovite–Lithuanian Wars (also known as "Russo-Lithuanian Wars", or just either "Muscovite Wars" or "Lithuanian Wars") were a series of wars between the Grand Duchy of Lithuania, allied with the Kingdom of Poland, and the Grand Duchy of Moscow.  After several defeats at the hands of Ivan III and Vasily III, the Lithuanians were increasingly reliant on Polish aid, which eventually became an important factor in the creation of the Polish–Lithuanian Commonwealth.  Before the first series of wars in the 15th century, the Grand Duchy of Lithuania had already gained control of a lot of Rus' territories, from Kiev to Mozhaisk, following the collapse of Kievan Rus' after the Mongol invasions.  Over the course of the series of wars, particularly in the 16th century, the Muscovites were able to expand their domain westwards, taking control of many Rus' lands.

Lipka Tatars: The Lipka Tatars (also known as Lithuanian Tatars, Polish Tatars, "Lipkowie", "Lipcani" or "Muślimi") are a group of Tatars who originally settled in the Grand Duchy of Lithuania at the beginning of the 14th century.  The first settlers tried to preserve their shamanistic religion and sought asylum amongst the non-Christian Lithuanians.  Towards the end of the 14th century, another wave of Tatars – this time, Muslims, were invited into the Grand Duchy by Vytautas the Great.  These Tatars first settled in Lithuania proper around Vilnius, Trakai, Hrodna and Kaunas and later spread to other parts of the Grand Duchy that later became part of Polish–Lithuanian Commonwealth.  These areas comprise present-day Lithuania, Belarus and Poland.  From the very beginning of their settlement in Lithuania they were known as the Lipka Tatars.  While maintaining their religion, they united their fate with that of the mainly Christian Polish–Lithuanian Commonwealth.  From the Battle of Grunwald onwards the Lipka Tatar light cavalry regiments participated in every significant military campaign of Lithuania and Poland.

History of Lithuania: The history of Lithuania dates back to settlements founded many thousands of years ago , but the first written record of the name for the country dates back to 1009 AD.  Lithuanians, one of the Baltic peoples, later conquered neighboring lands and established the Grand Duchy of Lithuania in the 13th century (and also a short-lived Kingdom of Lithuania).  The Grand Duchy was a successful and lasting warrior state.  It remained fiercely independent and was one of the last areas of Europe to adopt Christianity (beginning in the 14th century).  A formidable power, it became the largest state in Europe in the 15th century through the conquest of large groups of East Slavs who resided in Ruthenia.  In 1385, the Grand Duchy formed a dynastic union with Poland through the Union of Krewo.  Later, the Union of Lublin (1569) created the Polish–Lithuanian Commonwealth that lasted until 1795, when the last of the Partitions of Poland erased both Lithuania and Poland from the political map.  Afterward, the Lithuanians lived under the rule of the Russian Empire until the 20th century.

Duchy of Lithuania: Duchy of Lithuania (Latin: "Ducatus Lithuaniae" ; Lithuanian: "Lietuvos kunigaikštystė" ) was a state-territorial formation of ethnic Lithuanians, that existed from the 13th century until 1413.  Most of the time it was a constituent part and a nucleus of the Grand Duchy of Lithuania.  Other alternative names of the territorial formation, used in different periods, were Aukštaitija or Land of Lithuania (13th century), Duchy of Vilnius (14th – early 15th centuries), Lithuania Propria or simply Lithuania (in a narrow sense).

Lithuania proper: Lithuania proper (Latin: "Lithuania propria" , literally: "Genuine Lithuania"; Lithuanian: "Didžioji Lietuva" ; Yiddish: ליטע‎ , "Lite") refers to a region which existed within the Grand Duchy of Lithuania, and where the Lithuanian language was spoken.  The primary meaning is identical to the Duchy of Lithuania, a land around which the Grand Duchy of Lithuania evolved.  The territory can be traced by Catholic Christian parishes established in pagan Baltic lands of the Grand Duchy of Lithuania subsequent to the Christianization of Lithuania in 1387.  They were quite distinguishable, since Ruthenian parts of the Duchy have been already baptised in an orthodox manner.  The term in Latin was widely used during the Middle Ages and can be found in numerous historical maps until World War I.

Helena of Moscow: Helena Ivanovna of Moscow (Russian: Елена Ивановна ; Lithuanian: "Elena" ; Polish: "Helena Moskiewska" ; 19 May 1476 – 20 January 1513) was daughter of Ivan III the Great, Grand Prince of Moscow, and an uncrowned Grand Duchess of Lithuania and Queen of Poland as she would not convert from Eastern Orthodoxy to Catholicism.  Her childless marriage to Grand Duke of Lithuania and later King of Poland Alexander Jagiellon was a constant source of tension between the Grand Duchy of Moscow and the Grand Duchy of Lithuania.  Instead of guaranteeing peace, Helena's marriage gave her father Ivan III an excuse to interfere in Lithuanian affairs accusing Alexander of mistreating Helena and repressing Orthodox believers.  This became the pretext to renew the Muscovite–Lithuanian War in 1500.  The war ended with a six-year truce in 1503; the Grand Duchy of Lithuania lost about a third of its territory.  Despite political tensions and religious differences, the marriage was a loving one and the royal couple was close.  After her husband's death in 1506, Helena wanted to return to Moscow but was not allowed.  When she planned to run away, she was arrested and reportedly poisoned.

Supporting paragraphs: Lithuania proper Duchy of Lithuania
Answer: 13th century