Few events in human history transformed the world like the Bolshevik Revolution of 1917. Leading to the birth of the Soviet Union and the eventual creation of the Communist bloc, it was an event which defined the course of the 20th century.

The revolution which toppled the Russian Provisional Government and opened the way for Bolshevik takeover of the nation took place on November 7, 1917. However, since at that time Russia was still using the now-obsolete Julian calendar, inside the country the date was October 25. As a result, the historic event became known as the October Revolution, or to use the style later adopted in the USSR, the Great October Socialist Revolution.