The October Revolution, also known as the Great October Socialist Revolution (in Soviet historiography), October coup, Bolshevik coup, or Bolshevik revolution, was the second of two revolutions in Russia in 1917. It was led by Vladimir Lenin's Bolsheviks as part of the broader Russian Revolution of 1917–1923. It began through an insurrection in Petrograd (now Saint Petersburg) on 7 November 1917 [O.S. 25 October]. It was the precipitating event of the Russian Civil War. The initial stage of the October Revolution, which involved the assault on Petrograd, occurred largely without any casualties.
The October Revolution followed and capitalised on the February Revolution earlier that year, which had led to the abdication of Nicholas II and the creation of the Russian Provisional Government. The provisional government, led by Alexander Kerensky, had taken power after Grand Duke Michael, the younger brother of Nicholas II, declined to take power. During this time, urban workers began to organize into councils (soviets) wherein revolutionaries criticized the provisional government and its actions. The provisional government remained unpopular, especially because it was continuing to fight in World War I, and had ruled with an iron fist throughout mid-1917 (including killing hundreds of protesters in the July Days). It declared the Russian Republic on 1 [N.S. 14] September 1917.