Vladimir Lenin, leader of the revolutionary Bolshevik Party, arrived in Petrograd (now St. Petersburg), on April 16, 1917, after 10 years in exile and one month after the Tsar's forced abdication. He immediate published his "April Thesis", calling for "all power to the soviets"; pushing the Bolshevik party toward a confrontational stance leading to the October Revolution.
Lenin was born Vladimir Ilyich Ulyanov in 1870. His brother was executed in 1887 for plotting to assassinate Czar Alexander III causing Lenin to embrace revolutionary politics. Lenin studied law and practiced in Petrograd, where he moved in revolutionary Marxist circles. He was arrested and exiled to Siberia for three years for leading the "Union for the Struggle for the Liberation of the Working Class" After his exile ended in 1900, Lenin went to Western Europe, where he continued his revolutionary activity and adopted the pseudonym Lenin. He continued to build the Bolshevik party to topple the Tsarist government. He opposed WWI referring to it as a Capitalist war, staying in Europe to avoid persecution until his return to Russia in 1917.