The title "Queen of Bulgaria" refers to the female monarch of the Kingdom of Bulgaria, which existed from 1908 until 1946. The most notable queen was Queen Marie of Romania, who was married to King Ferdinand I and played a significant role in the country's political and cultural life during her reign. After the abolition of the monarchy in 1946, Bulgaria became a republic, and the title of queen ceased to exist. The last reigning queen was Queen Giovanna, the wife of King Boris III, who ruled from 1918 until his death in 1943.