German economist, philosopher, and revolutionary.With the help and support of Friedrich Engels, he wrote The CommunistManifesto (1848) and Das Kapital (1867-1894). These works establishedMarxism, the fundamental theory of Communism. Basically, Marxism explainspolitical, social, historical, and economic development in terms of theclass struggle between capitalists and the workers, or proletariat.Marxism predicted that capitalism would inevitably destroy itself andbourgeois oppression would make way for the rule of the proletariat. Thisnew age would be classless and free of economic exploitation, as all meansof production would be owned in common rather than individually.

In Russia, the doctrines of Marx were further developed and applied byVladimir Lenin, leader of the Bolshevik Revolution (1917) andfirst leader of the U.S.S.R. (1917-1924). Unlike some Marxists, Leninstressed revolutionary action rather than waiting for the inevitable fallof capitalism. Another distinction between Marxism and Leninism is wherethe action takes place. Marx held that Communism could only come about incapitalist nations that had achieved a high level of industrialdevelopment. Russia, of course, was largely an agrarian nation at the turnof the century, so Lenin adapted Marxism to apply to underdevelopedcountries. Lenin also believed that a strong Communist party was necessaryin a Marxist nation to direct the efforts of the workers. Eventually,according to Lenin, the state would "wither away" and rigid governmentalstructures would disappear.

After Lenin's death in 1924, the Soviet Union was led by Josef Stalin. His rule was marked by a purge of the government andmilitary, the forced collectivization of agriculture, a policy ofindustrialization, and the rigid control of the economy by the state.Stalin led the Soviet Union in its costly victory in World War II, (knownin the Soviet Union as the "Great Patriotic War").

Nikita Khrushchev became leader of the Soviet Union afterStalin's death in 1953. Khrushchev led a campaign of de-Stalinization,denouncing the late leader in his so-called "secret speech" of 1956. Whilespelling out Stalin's crimes, Khrushchev did not question the basicsoundness of Marxism-Leninism. Khrushchev urged peaceful coexistencebetween his country and Western nations. However, he sent Soviet troops toHungary in 1956 to crush an anti-Communist uprising and also aided thegovernment of Fidel Castro in Cuba. Because of his failure to improve theSoviet economy, Khrushchev was deposed in 1964.