Communism as an ideology arose in the wake of the first Industrial Revolution when overworked, underpaid workers felt exploited and sought better representation in government. The Communist Manifesto, as laid out by Karl Marx and Friedrich Engels, called for a classless society where each person would contribute according to ability and receive according to his or her needs.

While Marx never saw communism in action in his lifetime, Vladimir Lenin led the October Revolution in Russia in 1917, overthrowing imperial rule and establishing the Communist Party of the Soviet Union. Communism then spread to China and on to Cuba, Vietnam and Korea.

The original, higher vision of communism, as outlined by Marx and Engels, was never implemented. But a series of leaders and dictators from the Soviet Union to China to Cuba would label their governments as communist. Many of these leaders, including Joseph Stalin and Mao Zedong, were brutal in their rule, overseeing the mass murder of millions of their own citizens. They also came to represent one side of the Cold War with the United States.