Charles XIII was the King of Sweden from 1809 until his death in 1818. He was born on October 7, 1748, and became king after a coup that deposed his predecessor, Charles XIV John. His reign was marked by significant political changes, including the adoption of a new constitution in 1809 that established a parliamentary system. During his rule, Charles XIII also played a crucial role in the Napoleonic Wars, aligning Sweden with the coalition against Napoleon Bonaparte. He was the last king of the House of Pfalz-Zweibrücken and was succeeded by his adopted son, Charles XIV John, who founded the House of Bernadotte.