Jagiełłon

Jagiełłon, dynasty that ruled Poland from 1386 to 1572, also ruling Lithuania for most of this period, and at times Prussia, Bohemia, and Hungary. Founded in 1386 by the marriage of the Lithuanian prince Jagiełło to the Polish queen Jadwiga, the Jagiełłon dynasty made Poland-Lithuania a powerful state in early modern Europe.

Upon ascending the throne, Jagiełło took the name Władysław II Jagiełło and converted to Christianity. Pagan Lithuania soon followed his example by becoming a Christian country. For most of the reign of the dynasty, the two countries were united in the person of the common monarch, though the sovereign usually ruled Lithuania through a grand duke. The personal union of Jagiełłon sovereigns turned the Polish-Lithuanian monarchy into a great power. At the Battle of Tannenberg (Grunwald) in 1410, the combined Polish and Lithuanian armies defeated the Teutonic Knights, checking their expansionist tendencies. After Władysław II’s death in 1434, his son Władysław III became King of Hungary in 1440, but died in 1444 fighting the Ottoman Empire. Casimir IV was elected by the Poles to succeed Władysław III; he weakened the Teutonic Knights with a protracted war that secured vital territory by the Treaty of Toruń in 1466. It was Sigismund I, The Old, who finally broke the power of the Teutonic Knights by making Prussia a fief of Poland in 1525. Despite intermittent war with Russia in the east, the Jagiełłon dynasty acquired and secured a vast amount of territory in east-central Europe. Another branch of the dynasty, beginning with Władysław of Bohemia (king 1471-1516) and Hungary (king 1490-1516), ruled Bohemia and Hungary, but the line ended with the death of his son Louis II at the Battle of Mohács in 1526.

Internally, the dynasty lost political influence to the powerful aristocracy and gentry. The power of Jagiełłon kings gradually shifted to the parliamentary body of the nobility, the Sejm. The Reformation saw the rise of Protestantism in the liberal climate of 16th-century Poland-Lithuania, only to give way to Counter-Reformation Roman Catholicism. The Jagiełłon dynasty’s most important legacy was associated with the Renaissance; it produced in the 15th and 16th centuries a political and cultural golden age, typified by scholars such as Nicolaus Copernicus.

The last of the Jagiełłons, Sigismund II Augustus, formally joined the Kingdom of Poland and the Grand Duchy of Lithuania at the Union of Lublin in 1569. The creation of the Polish-Lithuanian Commonwealth was the last great achievement of the dynasty, as Sigismund II died heirless in 1572.