Georgi Valentinovich Plekhanov (Георгий Валентинович Плеханов) (December 11, 1856 – May 30, 1918; Old Style: November 29, 1856 – May 17, 1918) was a Russian revolutionary and a Marxist theoretician. He was a founder of the Social-Democratic movement in Russia.
Plekhanov contributed many ideas to Marxism in the area of philosophy and the roles of art and religion in society. In his political activities he adopted the nom de guerre of Volgin, after the Volga River. Some have commented that this name influenced the famous revolutionary Vladimir Ilyich Ulyanov adopting the name Lenin to highlight his opposition to Plekhanov's politics. This claim is however refuted due to the timing involved. The first instance of Lenin's pseudonym predates any disagreement with Plekhanov.
Plekhanov was originally a Narodnik, a leader of the organization "Land and Liberty". After emigrating from Russia in 1880, he established connections with the Social-Democratic movement of western Europe and began to study the works of Marx and Engels. This led him to renounce Narodism and become a Marxist.
In 1883 in Switzerland, he co-founded with Lev Deutsch and Vera Zasulich, the "Emancipation of Labor" group, which popularized Marxism among Russian revolutionaries. At its dissolution, he joined the Russian Social Democratic Labour Party (RSDLP) and worked with Lenin.
In 1903, at the second congress of the RSDLP, Plekhanov broke with Lenin and sided with the Mensheviks. During World War I, he took a "nationalist" position (as opposed to the Bolsheviks' "proletarian internationalism"), calling for the defeat of Germany. This owed him Lenin's critics as a "Social-Chauvinist" in the April's Theses, which quoted Plekhanov claiming that Lenin was advocating "civil war" in the socialist movement by his supporting the creation of a new International consequently to the 1915 Zimmerwald Conference and the subsequent dissolving, in 1916, of the Second International.
He returned to Russia after the February Revolution and formed Yedinstvo. However, he left Russia again after the October Revolution because he was hostile toward the Bolsheviks. He died of tuberculosis in Terijoki, Finland (now Zelenogorsk, Saint Petersburg, Russia). Despite his disagreements with Lenin, the Soviet Communists cherished his memory and gave his name to the Soviet Academy of Economics and the G.V. Plekhanov St. Petersburg State Mining Institute.