Jogaila, also known as Władysław II Jagiełło, was a significant historical figure who became the Grand Duke of Lithuania and later the King of Poland. He was born around 1351 and played a crucial role in the unification of Poland and Lithuania through his marriage to Queen Jadwiga in 1386. This union marked the beginning of the Jagiellonian Dynasty, which ruled both countries for several centuries. Under Jogaila's leadership, the Polish-Lithuanian alliance became a powerful force in Eastern Europe. He is best known for his victory at the Battle of Grunwald in 1410 against the Teutonic Knights, which significantly weakened their influence in the region. Jogaila's reign contributed to the cultural and political development of both nations, establishing a legacy that would last long after his death in 1434.