Grand Dukes of Lithuania - History - Kingdom of Lithuania

Kingdom of Lithuania

Mindaugas, duke of southern Lithuania, was among the five senior dukes, mentioned in the treaty with Galicia–Volhynia. According to the Livonian Rhymed Chronicle, by mid-1230s Mindaugas acquired supreme power in the whole of Lithuania. In 1236, the Samogitians, led by Vykintas, defeated the Livonian Order in the Battle of Saule. The Order was forced to become a branch of the Teutonic Knights in Prussia. That meant that Samogitia, a strip of land that separated Livonia from Prussia, became the main target of both orders. The battle provided a break in the wars with the Knights and Lithuania exploited this situation, arranging attacks towards the Ruthenian provinces and annexing Navahrudak and Hrodna.

In 1248 a civil war broke out between Mindaugas and his nephews Tautvilas and Edivydas. The powerful coalition against Mindaugas included Vykintas, the Livonian Order, Daniel of Galicia, and Vasilko of Volhynia. Mindaugas, taking advantage of internal conflicts, allied with the Livonian Order. He promised to convert to Christianity and gift some lands in western Lithuania in exchange for military assistance against his nephews and the royal crown. In 1251 Mindaugas was baptized and Pope Innocent IV issued a papal bull, proclaiming the creation of the Kingdom of Lithuania. After the civil war ended, Mindaugas was crowned as King of Lithuania on July 6, 1253, starting a decade of relative peace. Mindaugas tried to expand his influence in Polatsk, a major center of commerce in the Daugava River basin, and Pinsk. The Teutonic Knights used this period to strengthen its position in parts of Samogitia and Livonia, but lost the Battle of Skuodas in 1259 and the Battle of Durbe in 1260. These losses encouraged conquered Semigallians and Prussians to rebel against the Knights.

Encouraged by Treniota, Mindaugas broke the peace with the Order, possibly relapsed into his old beliefs, and allied with Alexander Nevsky of Novgorod. He hoped to unite all Baltic tribes under the Lithuanian leadership. As military campaigns were not successful, the relationships between Mindaugas and Treniota deteriorated. Treniota together with Daumantas assassinated Mindaugas and his two sons, Ruklys and Rupeikis, in 1263. The state lapsed into years of internal fights.