The Russian Revolution began in 1917, with two major events: the February Revolution and the October Revolution. The February Revolution led to the abdication of Tsar Nicholas II and the establishment of a provisional government, while the October Revolution, led by the Bolsheviks under Vladimir Lenin, resulted in the overthrow of that government and the establishment of a socialist regime. The revolution was significant because it dismantled the autocratic Tsarist rule and led to the creation of the Soviet Union, fundamentally altering the political landscape of Russia and influencing revolutionary movements worldwide for much of the 20th century.