Casimir IV Jagiellon was a significant monarch of the Polish-Lithuanian Commonwealth, reigning from 1447 to 1492. He was a member of the Jagiellon dynasty and is known for strengthening the state through military victories and diplomatic efforts. His reign marked a period of territorial expansion and increased influence in Central Europe. Under Casimir IV's leadership, the Commonwealth experienced economic growth and cultural development. He supported the University of Kraków, promoting education and the arts. His efforts helped solidify the union between Poland and Lithuania, making him a key figure in the history of both nations.