From 1917 to 1918, through a series of turbulent events that included two separate and distinct revolutions in Petrograd -- St. Petersburg -- Russia went from being a monarchy to becoming world's first Marxist state. The second revolution established Vladimir Lenin, leader of a radical political group known as the Bolsheviks, as the dictator of a communist nation that in 1922 adopted the name Union of Soviet Socialist Republics.

Bolsheviks vs. Mensheviks

In 1903, London and Brussels hosted the second congress of the Russian Social-Democratic Workers’ Party, a Marxist group. The gathering exposed a critical divide among its members that resulted in the party splitting into two factions: the Bolsheviks and the Mensheviks. The former, led by Lenin, wanted party membership to consist exclusively of professional revolutionaries and keep power centralized; the latter wanted to run the party democratically and allow anyone to join their ranks. The Bolsheviks sought to establish a dictatorship of the working class, or proletariat. The Mensheviks, on the other hand, envisioned a gradual move to socialism beginning with a revolution of the middle class, or the bourgeois, followed by a transitional period of capitalism.

February Revolution

In March 1917 -- February in Russia, which used the Julian calendar -- a popular uprising in Petrograd supported by factory workers forced Czar Nicholas II to step down, marking the end of the country's history of monarchical rule. In the wake of the revolt, a provisional government consisting of members of the Duma, or state legislature, vied for power with a more radical labor union of workers and soldiers known as the Petrograd Soviets. Both entities worked together, however, and agreed that a somewhat democratic system should replace the monarchy.

October Revolution

The February Revolution prompted Lenin's return to Russia in April. He immediately condemned the collaboration between the provisional government and the Petrograd Soviet and began organizing Bolshevik opposition accordingly. After a few failed attempts at inciting an overthrow, in November, in what is known as the October Revolution, the Bolsheviks seized the Winter Palace and other government buildings in Petrograd. With little resistance from the provisional government, Lenin was henceforth the head of a Marxist country, the first of its kind.

Russian Civil War

While few lives were lost in the October Revolution in which the Bolsheviks came to power, the opposite is true of the civil war that followed. In March 1918, Lenin's government signed the Treaty of Brest-Litovsk, which ended Russia's military involvement in World War I, but in the process made enormous territorial concessions to Germany and its fellow Central Powers. The treaty further incensed Lenin's opponents and by summer, Russia had descended into a civil war between the Bolsheviks, or the Reds, and a coalition of anti-Bolshevik interest groups collectively known as the Whites. An unsuccessful assassination attempt on Lenin in August triggered the Red Terror, the ruthlessly violent suppression of anyone who opposed the Bolsheviks. The Bolsheviks emerged victorious in 1921, allowing Lenin to consolidate his dictatorship.