King Charles X Gustav was the King of Sweden from 1654 until his death in 1660. He belonged to the House of Palatinate-Zweibrücken and was known for his military campaigns during the Northern Wars. His reign was marked by efforts to strengthen Sweden's position as a major power in Europe. Charles X Gustav is best remembered for his successful invasion of Poland and his role in the Second Northern War. His aggressive foreign policy aimed to expand Swedish territory, but it also led to conflicts with neighboring countries. His reign ended with his untimely death, leaving a mixed legacy.