King Alexander I of Yugoslavia, born in 1888, was the monarch of the Kingdom of Serbs, Croats, and Slovenes, later known as Yugoslavia. He ascended to the throne in 1921 and worked to unify the diverse ethnic groups within the kingdom. His reign was marked by efforts to promote national unity and modernization. In 1934, King Alexander was assassinated in Marseille, France, during a state visit. His death led to political instability in Yugoslavia, and his son, King Peter II, succeeded him. Alexander's legacy includes his attempts to create a cohesive Yugoslav identity amid regional tensions.