The Battle of Moon Sound was a naval battle fought between the forces of the German Empire, and the then Russian Republic (and three British submarines) in the Baltic Sea during Operation Albion from 16 October 1917 until 3 November 1917 during World War I. The German intention was to destroy the Russian forces and occupy the West Estonian Archipelago. The Imperial German Navy had one battlecruiser, 10 battleships, nine light cruisers, one mine cruiser, 50 destroyers and six submarines while the Russians had only two pre-dreadnoughts, three cruisers, three gunboats, 21 destroyers, plus three British submarines.