Ladislaus II (king of Poland)
Ladislaus II or Ladislaus Jagiello (yägyĕ´lō), 1350?–1434, king of Poland (1386–1434), grand duke of Lithuania (1378–1401), founder of the Jagiello dynasty. Leaguing with Poland against the menacing Teutonic Knights, he acceded to the Polish throne by marrying Queen Jadwiga. Baptized at this time, he agreed to convert Lithuania to Christianity. The union of Poland and Lithuania continued after he delegated (1401) a cousin as grand duke. Jagiello's victory over the Teutonic Knights at Tannenberg (1410) resulted in the First Peace of Toruń in 1411. His son by a later wife, Ladislaus III, succeeded him as Polish king.