Casimir IV Jagiellon
Casimir IV was grand duke of Lithuania at thirteen and king of Poland at nineteen, fought the Teutonic Order for thirteen years and took Prussia and Danzig from it, married a Habsburg and put four sons on four thrones, and paid for the wars by conceding to the Polish gentry the privileges that made the Sejm the master of the kings after him. He was born in 1427, the younger son of Jagiełło, and was sent to Lithuania in 1440 as his brother's viceroy. The Lithuanian lords crowned him grand duke instead, and when the brother was killed at Varna in 1444 the Poles waited three years for him to accept their crown on his terms, which were that the union would be personal and Lithuania would keep its lands. In 1454 the towns and gentry of Prussia rose against the Teutonic Order and asked to join Poland, and the Thirteen Years' War that followed was fought with mercenaries the Sejm would only pay for if the king signed the statutes of Nieszawa, which bound him to call the provincial diets before raising taxes or armies. The Second Peace of Thorn in 1466 gave Poland Royal Prussia with Danzig, Elbing and Marienburg, and left the Order the east as a Polish fief, so that Poland had the Baltic and the grand masters knelt to its kings. He married Elisabeth of Habsburg in 1454 and had thirteen children, and used them. Vladislaus was king of Bohemia from 1471 and of Hungary from 1490, three others reigned in Poland in turn, one was a cardinal and one a saint, and the daughters married across Germany. He fought the Hungarians in Silesia, kept the Tatars off with tribute, lost his Black Sea ports to the Ottomans, and let the chancellor Oleśnicki's successors run the church. The Sejm met regularly from 1493, the year after he died, as two chambers, which is the date Polish parliamentarism is counted from. He died at Grodno in June 1492 and lies at Wawel under a tomb Veit Stoss carved, whose opening in 1973 killed several of the scientists who breathed its fungus.
- Lived: 1427 CE – 1492 CE
- Nationality: Polish
- Roles: king, monarch
