Leon Trotsky

Lev Davidovich Bronstein (7 November 1879 – 21 August 1940), known as Leon Trotsky, was a Russian Marxist revolutionary and political theorist of Jewish origin born in Yanovka, Ukraine, then part of the Russian Empire. He became a central figure in the Bolshevik faction of the Russian Social Democratic Labour Party and, after joining the Bolsheviks in 1917, served as chairman of the Petrograd Soviet, organizing the armed insurrection that led to the October Revolution and the overthrow of the Provisional Government. Appointed People's Commissar for Foreign Affairs in the first Soviet government, Trotsky negotiated the Treaty of Brest-Litovsk to exit World War I, then as People's Commissar for War from 1918 to 1925 founded and commanded the Red Army, which defeated anti-Bolshevik forces in the Russian Civil War.

Trotsky developed the theory of permanent revolution, arguing that socialist transformation in less-developed countries like Russia required continuous proletarian leadership and international extension to survive, contrasting with Joseph Stalin's doctrine of socialism in one country. After Lenin's death in 1924, Trotsky lost the succession struggle to Stalin, who expelled him from the Communist Party in 1927 and exiled him from the Soviet Union in 1929; Trotsky then founded the Fourth International to promote global Trotskyism. Relocated to Mexico in 1937, he continued critiquing Stalinism until his assassination on 21 August 1940 by Ramón Mercader, a Soviet NKVD agent acting on Stalin's orders. Trotsky's writings, including The Revolution Betrayed, analyzed the Soviet bureaucracy's degeneration into totalitarianism, influencing leftist opposition movements worldwide.