The Gangut was a Sevastopol-class battleship of the Russian Imperial Fleet. She was laid down on June 16, 1909; launched on October 20, 1911; and commissioned in late December 1914. In August 1915, the Gangut and the Sevastopol sailed into the Baltic Sea to provide cover for a mine-laying operation. Due to bad weather, both battleships sustained minor underwater damage. In late October 1915, sailors on the Gangut spontaneously revolted, and the uprising quickly escalated into riots. The battleships remained moored off Helsinki in 1916 and 1917, not sailing. In accordance with the terms of the Treaty of Brest-Litovsk, all battleships were withdrawn from Helsinki and relocated to Kronstadt by March 17, 1918. In late October and early November 1918, the Gangut was transferred to the Admiralty Shipyard for "long-term storage". On April 18, 1925, Gangut was finally towed to Kronstadt to restore her combat readiness. On July 7, she was renamed Oktyabrskaya Revolyutsiya. The ship returned to service on July 23, 1926.

A large-scale modernization of the battleship began in September 1931. It was completed over four winters from 1931 to 1934. The modernization was significant. Her speed and range increased, her fire control system was updated, her seaworthiness improved, and her armor was reinforced. Minor modifications and repairs were carried out every winter until the late 1930s. At the start of World War II, the battleship was stationed at Tallinn Roads. In early July, having encountered no resistance, it transferred to Kronstadt. In late July, the battleship began firing on German units advancing on Leningrad. In September, the battleship begun to be subjected to air raids. On September 21, she sustained significant damage to her forecastle due to a concentrated bomb hit. In late October 1941, the battleship moved to Leningrad for repairs. During this time, the ship's anti-aircraft battery was reinforced and her deck armor improved. In 1944, the battleship provided support to ground forces during the lifting of the siege of Leningrad and shelled fortifications on the Karelian Isthmus. During the postwar period, the ship underwent only routine repairs and had radars installed. On April 10, 1956, the battleship was decommissioned. On November 1, she was towed to the Glavvtorchermet base in Leningrad for scrapping.

The Oktyabrskaya Revolyutsiya was introduced as the main prize of the 2026 "Defender of the Baltic Sea" event. The battleship was introduced after the post-war modernization and possesses a very capable anti-aircraft battery, along with powerful main battery guns and reinforced horizontal armor. However, it retains a very low speed, an inconveniently positioned main battery, and weak vertical armor.