The Soviet Navy was divided into four major fleets: the Northern, Pacific, Black Sea, and Baltic Fleets; under separate command was the Leningrad Naval Base. The Caspian Flotilla was a smaller force operating in the land-locked Caspian Sea. Main components of the Soviet Navy included Soviet Naval Aviation, Naval Infantry (Soviet Marines), and Coastal Artillery.
After the dissolution of the Soviet Union in 1991, Russia inherited the largest part of the Soviet Navy and reformed it into the Russian Navy, with smaller parts becoming the basis for navies of the newly independent post-Soviet states.
The Soviet Navy was based on a republican naval force formed from the remnants of the Imperial Russian Navy, which had been almost completely destroyed in the two Revolutions of 1917 (February and October/November) during World War I (1914-1918), the following Russian Civil War (1917-1922), and the Kronstadt rebellion in 1921. During the revolutionary period, Russian sailors deserted their ships at will and generally neglected their duties. The officers were dispersed (some were killed by the Red Terror, some joined the "White" (anti-communist) opposing armies, and others simply resigned) and most of the sailors left their ships. Work stopped in the shipyards, where uncompleted ships deteriorated rapidly.
The Black Sea Fleet fared no better than the Baltic. The Bolshevik (Communist) revolution entirely disrupted its personnel, with mass murders of officers; the ships were allowed to decay to unserviceability. At the end of April 1918, Imperial German troops moved along the Black Sea coast and entered Crimea and started to advance towards the Sevastopol naval base. The more effective ships were moved from Sevastopol to Novorossiysk where, after an ultimatum from Germany, they were scuttled by Vladimir Lenin's order. The ships remaining in Sevastopol were captured by the Germans and then, after the Armistice of 11th November 1918 on the Western Front, by the British. On 1 April 1919, during the ensuing Russian Civil War when Red Army forces captured Crimea, the British Royal Navy squadron had to withdraw, but before leaving they damaged all the remaining battleships and sank thirteen new submarines. When the opposing Czarist White Army captured Crimea in 1919, it rescued and reconditioned a few units. At the end of the civil war, Wrangel's fleet, a White flotilla, moved south through the Black Sea, Dardanelles straits and the Aegean Sea to the Mediterranean Sea to Bizerta in French Tunisia on the North Africa coast, where it was interned.
The first ship of the revolutionary navy could be considered the rebellious Imperial Russian cruiser Aurora, built 1900, whose crew joined the communist Bolsheviks. Sailors of the Baltic fleet supplied the fighting force of the Bolsheviks led by Vladimir Lenin and Leon Trotsky during the October Revolution of November 1917 against the democratic provisional government of Alexander Kerensky established after the earlier first revolution of February against the Czar. Some imperial vessels continued to serve after the revolution, albeit with different names.