Mindaugas (c. 1203 – 12 September 1263) was the first known Grand Duke of Lithuania and the only crowned King of Lithuania. Little is known of his origins, early life, or rise to power; he is mentioned in a 1219 treaty as an elder duke, and in 1236 as the leader of all the Lithuanians. The contemporary and modern sources discussing his ascent mention strategic marriages along with banishment or murder of his rivals. He extended his domain into regions southeast of Lithuania proper during the 1230s and 1240s. In 1250 or 1251, during the course of internal power struggles, he was baptised as a Roman Catholic; this action enabled him to establish an alliance with the Livonian Order, a long-standing antagonist of the Lithuanians. By 1245, Mindaugas was already being referred to as "the highest king" in certain documents. During the summer of 1253, he was crowned king, ruling between 300,000 and 400,000 subjects, and was nicknamed as Mindaugas the Sapient by the Livonians.
While Mindaugas's reign as king was marked by many state-building accomplishments, his conflicts with relatives and other dukes continued. The western part of Lithuania – Samogitia – strongly resisted the alliance's rule. His gains in the southeast were challenged by the Tatars. He broke peace with the Livonian Order in 1261, possibly renouncing Christianity, and was assassinated in 1263 by his nephew Treniota and another rival, Duke Daumantas of Pskov. His three immediate successors were assassinated as well. The disorder was not resolved until Traidenis gained the title of grand duke c. 1270.
Although his reputation was unsettled during the following centuries and his descendants were not notable, he gained standing during the 19th and 20th centuries. Mindaugas was the only king of Lithuania; while most of the Lithuanian grand dukes from Jogaila onward also reigned as kings of Poland, the titles remained separate. Now generally considered the founder of the Lithuanian state, he is also now credited with stopping the advance of the Tatars towards the Baltic Sea, establishing international recognition of Lithuania, and turning it towards Western civilization. In the 1990s the historian Edvardas Gudavičius published research supporting an exact coronation date – 6 July 1253. Although disputed, this day is now an official national holiday in Lithuania, Statehood Day.
Contemporary written sources about Mindaugas are very scarce. Much of what is known about his reign is obtained from the Livonian Rhymed Chronicle and the Hypatian Codex. Both of these chronicles were produced by enemies of Lithuania and thus have anti-Lithuanian bias, particularly the Hypatian Codex. They are also incomplete: both of them lack dates and locations even for the most important events. For example, the Livonian Rhymed Chronicle devoted 125 poetry lines to Mindaugas's coronation, but failed to mention either the date or the location.
Kronika polska, litewska, żmódzka i wszystkiej Rusi, published by Maciej Stryjkowski in 1582, asserts that in 1240 Mindaugas ascended to his father's throne in Navahrudak. While ruling in Navahrudak and other Rus' castles, he began to eliminate his friends, seduced by the greed for power.
Boguchwala i Godyslawa Paska Chronicle describes Mindaugas as a ruthless king of Prussia, who, in 1260, withdrew from the Christian faith and obliterated Mazovian city Płock and Prussia committing a great slaughter among the Christian people. Other important sources are the papal bulls regarding baptism and coronation of Mindaugas. The Lithuanians did not produce any surviving records themselves, except for a series of acts granting lands to the Livonian Order, but their authenticity is disputed. Due to lack of sources, some important questions regarding Mindaugas and his reign cannot be answered.
Because written sources covering the era are scarce, Mindaugas's origins and family tree have not been conclusively established. The Bychowiec Chronicles, dating from the 16th and 17th centuries, have been discredited in this regard, since they assert an ancestry from the Palemonids, a noble family said to have originated within the Roman Empire. His year of birth, sometimes given as c. 1200, is at other times left as a question mark. His father is mentioned in the Livonian Rhymed Chronicle as a powerful duke (ein kunic grôß), but is not named; later chronicles give his name as Ryngold. Dausprungas, mentioned in the text of a 1219 treaty, is presumed to have been his brother, and Dausprungas' sons Tautvilas and Gedvydas his nephews. He is thought to have had two sisters, one married to Vykintas and another to Daniel of Halych. Vykintas and his son Treniota played major roles in later power struggles. Mindaugas had at least two wives, Morta and Morta's sister, whose name is unknown, and possibly an earlier wife; her existence is presumed because two children – a son named Vaišvilkas and an unnamed daughter married to Svarn in 1255 – were already leading independent lives when Morta's children were still young. In addition to Vaišvilkas and his sister, two sons, Ruklys and Rupeikis, are mentioned in written sources. The latter two were assassinated along with Mindaugas. Information on his sons is limited and historians continue to discuss their number. He may have had two other sons whose names were later conflated by scribes into Ruklys and Rupeikis.
In the 13th century Lithuania had little contact with foreign lands. Lithuanian names sounded obscure and unfamiliar to various chroniclers, who altered them to sound more like names in their native language. Mindaugas's name in historic texts was recorded in various distorted forms: Mindowe, Mendog, Mindog, Mendolphus in Latin; Mindouwe, Myndow, Myndawe, and Mindaw in German; Mendog, Mondog, Mendoch, and Mindovg in Polish; and Mindovg, Mindog, and Mindowh in Old Church Slavonic, among others. Since Old Church Slavonic sources provide the most information about Mindaugas's life, they were judged the most reliable by linguists reconstructing his original Lithuanian name. The most popular Old Church Slavonic rendition was Mindovg, which can quite easily and naturally be reconstructed as Mindaugas or Mindaugis. In 1909 the Lithuanian linguist Kazimieras Būga published a research paper supporting the suffix -as, which has since been widely accepted. Mindaugas is an archaic dithematic Lithuanian name, used before the Christianization of Lithuania, and consists of two components: min and daug. Its etymology may be traced to "daug menąs" (much wisdom) or "daugio minimas" (much fame).
Lithuania was ruled during the early 13th century by a number of dukes and princes presiding over various fiefdoms and tribes. They were loosely bonded by commonalities of religion and tradition, trade, kinship, joint military campaigns, and the presence of captured prisoners from neighboring areas. Western merchants and missionaries began seeking control of the area during the 12th century, establishing the city of Riga, Latvia in 1201. Their efforts in Lithuania were temporarily halted by defeat at the Battle of Saule in 1236, but armed Christian orders continued to pose a threat. The country had also undergone incursions by the Mongol Empire.
A treaty with Galicia–Volhynia, signed in 1219, is usually considered the first conclusive evidence that the Baltic tribes in the area were uniting in response to these threats. The treaty's signatories include twenty Lithuanian dukes and one dowager duchess; it specifies that five of these were elder and thus took precedence over the remaining sixteen. Mindaugas, despite his youth, as well as his brother Dausprungas are listed among the elder dukes, implying that they had inherited their titles. The Livonian Rhymed Chronicle describes him as the ruler of all Lithuania in 1236. His path to this title is not clear. Ruthenian chronicles mention that he murdered or expelled several dukes, including his relatives. Historian S.C. Rowell has described his rise to power as taking place through "the familiar processes of marriage, murder and military conquest." In Rowell's interpretation, Mindaugas recognized the advantage to Christianity in attracting foreign merchants and military support from the Teutonic Order. As a result, in 1251, he was baptised Catholic. The conversion was purely for political gain with Catholic Europe; Mindaugas was known to continue to sacrifice to his old gods after his "conversion." In order to consolidate his power, Mindaugas married into rival families, defeated some in battle, and exiled the rest of his rivals.