Jagiellon dynasty. Dynasty of Polish and Lithuanian monarchs, who ruled much of east-central Europe in the 15th and 16th centuries. The dynasty originated with Grand Duke Jogaila (Jagiełło) of Lithuania, who became King Władysław II of Poland (1386–1434) by marrying Queen Jadwiga. His successors were his sons Władysław III Warneńczyk of Poland (1434–44) and Hungary (1440–4) and Casimir IV Jagiellończyk of Lithuania (1440–92) and Poland (1447–92); Casimir's sons Jan I Olbracht of Poland (1492–1501), Alexander Jagiellończyk of Lithuania (1492–1506) and Poland (1501–6), and Sigismund I the Old of Poland and Lithuania (1506–48); and Sigismund's son Sigismund II Augustus of Poland and Lithuania (1548–72), with whom the Polish-Lithuanian dynasty came to an end. Casimir's fourth son, Władysław, was the king of Bohemia (1471–1516) and Hungary (1516–26); he was succeeded by his son Louis II (1516–26).
In Ukraine, Jagiellon rule was marked by the liquidation of the last independent (appanage) Lithuanian-Ruthenian principalities (see Lithuanian-Ruthenian state), the consolidation of Polish rule in the western Ukrainian lands, intensive Polonization, the imposition of Roman Catholicism and Germanic law and Magdeburg law, urban growth, significant economic development, and the enserfment of the peasantry.