King Peter I of Serbia

King Peter I of Serbia, who ruled from 1903 to 1918, was known for his efforts to modernize Serbia and promote democratic governance. He came to power after a coup that deposed the previous monarchy and was popular for advocating for the rights of the common people. Peter played a key role during World War I, aligning Serbia with the Allies against the Central Powers. After the war, he helped unite Serbia with other South Slavic nations, leading to the creation of the Kingdom of Serbs, Croats, and Slovenes, which later became Yugoslavia. He abdicated in 1921 and died in 1921.