Twentieth-century British history made simple

Peter I (Serbo-Croatian: Петар I Карађорђевић, romanized: Petar I Karađorđević; 11 July [O.S. 29 June] 1844 – 16 August 1921) was King of Serbia from 15 June 1903 to 1 December 1918. On 1 December 1918, he became King of the Serbs, Croats and Slovenes, and he held that title until his death three years later. Since he was the king of Serbia during a period of great Serbian military success, he was remembered by Serbians as King Peter the Liberator and also as the Old King. Peter was the fifth child and third son of Alexander Karađorđević, Prince of Serbia, and his wife, Persida Nenadović. Prince Alexander was forced to abdicate in 1858, and Peter lived with his family in exile.