Petar II of Yugoslavia was the last king of the Kingdom of Yugoslavia, reigning from 1934 until 1945. Born on September 6, 1923, he became king at just 11 years old after the assassination of his father, King Alexander I. His reign was marked by political instability and the rise of World War II. During the war, Petar II fled to London, where he led the Yugoslav government-in-exile. He struggled to unite various factions within Yugoslavia, including the Partisans and Chetniks. After the war, the monarchy was abolished, and he lived in exile until his death on November 3, 1970.