Vasa, House of

A royal dynasty with branches in Sweden and Poland, which reigned in the sixteenth and seventeenth centuries. The dynasty was founded in Sweden by Gustavus I. His son John married Catherine Jagellonica, the sister of King Sigismund II of Poland. John's brother, then the king of Sweden, bitterly opposed this marriage and confined the couple to the castle of Gripsholm, where their son Sigismund was born and was educated by fervently Catholic Jesuit priests.

In 1587 Sigismund was elected as King Sigismund III Vasa by the electors of the commonwealth of Poland. When his father King John III died, Sigismund also became the king of Sweden, but his attempts to return Sweden to the Catholic Church was opposed by the parliament of Sweden, which deposed him in 1599. In Poland, Sigismund led an attack on the Baltic state of Latvia, intending to annex it to Poland, in 1600. This provoked war with Sweden and a series of conflicts between the two Vasa dynasties that would continue for more than fifty years.

In Sweden Sigismund was succeeded by Charles IX, his uncle and a Protestant. Gustavus II Adolphus succeeded Charles. An able military commander, Gustavus led a powerful Swedish force against the Catholics in Germany and won key victories during the Thirty Years' War. On his death in battle in 1632 his daughter Christina became the queen of Sweden. Christina converted to Catholicism and abdicated the throne of Sweden in 1654, passing the monarchy to her cousin, Charles X, a member of the Wittelsbach dynasty of Germany. This event brought the Swedish Vasa dynasty to an end.

By the Peace of Westphalia, which ended the Thirty Years' War in 1648, Sweden had gained territory on the southern shores of the Baltic Sea—land that had long been claimed by the kings of Poland. In 1655 two large columns of Swedish troops invaded Poland, bringing Poland as well as Lithuania under Swedish control. The Polish line of the Vasa dynasty had continued through the reigns of Ladislav IV, who was succeeded in 1648 by his brother Jan II Kazimierz. This king escaped the Swedish assault of 1655 and from his refuge in Silesia called on the Polish nation to resist the Swedes. The uprising resulted in the Treaty of Oliwa in 1660, which returned Sweden and Poland to their original borders.

See Also: Sweden; Thirty Years' War