Władysław II Jagiełło
Jogaila, later Władysław II Jagiełło was the Grand Duke of Lithuania (1377–1434) and then the King of Poland (1386–1434), first alongside his wife Jadwiga until 1399, and then sole King of Poland. He ruled in Lithuania from 1377. Born a pagan, in 1386 he converted to Catholicism and was baptized as Władysław in Kraków, married the young Queen Jadwiga, and was crowned King of Poland as Władysław II Jagiełło. In 1387 he converted Lithuania to Christianity. His own reign in Poland started in 1399, upon the death of King Jadwiga, and lasted a further thirty-five years and laid the foundation for the centuries-long Polish–Lithuanian union. He was a member of the Jagiellonian dynasty in Poland that bears his name and was previously also known as the Gediminid dynasty in the Grand Duchy of Lithuania. The dynasty ruled both states until 1572, and became one of the most influential dynasties in late medieval and early modern Europe. During his reign, the Polish-Lithuanian state was the largest state in the Christian world.