John II Casimir Vasa (22 March 1609-16 December 1672) was King of Poland-Lithuania from November 1648 to 16 September 1668, succeeding Wladyslaw IV Vasa and preceding Michal Korybut Wisniowiecki.
Biography[]
John Casimir Vasa was born in Krakow, Poland in 1609, the son of King Sigismund III Vasa of Poland-Lithuania and Sweden and the younger half-brother of Wladyslaw IV Vasa. From 1632 to 1635, his brother failed to arrange his marriage to Christina of Sweden, and, in 1637, he abandoned a diplomatic mission to Vienna to serve in the Holy Roman Empire's army against France during the Thirty Years War. He returned to Poland-Lithuania in 1636, and the Sejm vetoed his brother's attempt to make him Duke of Courland. Taking offense at this, he traveled to Spain in 1638 to become Viceroy of Portugal, but he was captured by French agents and imprisoned until 1640. In 1641, John Casimir decided to become a Jesuit, and he was made a cardinal in 1643 before resigning in October 1647 to stand in elections for the Polish throne. He was elected with the support of the Austrian Habsburgs, succeeding his late half-brother. His reign was dominated by the Khmelnytsky Uprising in Ukraine, the Russo-Polish War from 1654 to 1667, "the Deluge" of Swedish invasions from 1655 to 1660, and rebellions by nobles who opposed his absolutist style of governance. In 1660, he was forced to renounce his claim to the Swedish throne and acknowledge Swedish sovereignty over Livonia, and he abdicated the throne in 1668 after his wife's death and rejoined the Jesuits in Paris. He died of apoplexy in 1672 before he could return to Poland.