Mindaugas (ca. 1200 – 12 September 1263) was the first known Grand Duke of Lithuania and the only 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. During the summer of 1253 he was crowned King of Lithuania, ruling between 300,000 and 400,000 subjects.
Mindaugas and his wife Morta were crowned during the summer of 1253. Bishop Henry Heidenreich of Kulm presided over the ecclesiastical ceremonies and Andreas Stirland conferred the crown. 6 July is now celebrated as Statehood Day (Lithuanian: Valstybės diena); it is an official holiday in modern Lithuania The exact date of the coronation is not known; the scholarship of historian Edvardas Gudavičius , who promulgated this precise date, is sometimes challenged. The location of the coronation also remains unknown.
Relative peace and stability prevailed for about eight years. Mindaugas used this opportunity to concentrate on the expansion to the east, and to establish and organize state institutions. He strengthened his influence in Black Ruthenia, in Polatsk, a major center of commerce in the Daugava River basin, and in Pinsk. He also negotiated a peace with Galicia-Volhynia, and married his daughter to Svarn, the son of Daniel of Galicia, who would later become Grand Duke of Lithuania. Lithuanian relationships with western Europe and the Holy See were reinforced. In 1255, Mindaugas received permission from Pope Alexander IV to crown his son as King of Lithuania A noble court, an administrative system, and a diplomatic service were initiated Silver long coins, an index of statehood, were issued. He sponsored the construction of a cathedral in Vilnius, possibly on the site of today's Vilnius Cathedral. The earliest religious texts in the Lithuanian language appeared at this time.
Immediately after his coronation, Mindaugas transferred some lands to the Livonian Order – portions of Samogitia, narduva, Selonia and Dainava — although his control over these western lands was tenuous There has been much discussion among historians as to whether in later years (1255, 1257, and 1259) Mindaugas gave even more lands to the order. The deeds might have been falsified by the order; the case for this scenario is bolstered by the fact that some of the documents mention lands that were not actually under the control of Mindaugas.
Days of Live Archaeology are organised at the foot of Gediminas Hill and in the Old Town where craftsmen demonstrate old crafts, knights can be seen standing in groups, participants listen to old music and are welcomed to the fairs, and concerts of ethnographical bands or other festivities are organised around the city.