During World War II, all civilian inhabitants of the island were relocated to the Japanese home islands, and towards the end of the war, the Imperial Japanese Army stationed approximately 6,000 troops on Uruppu, including the IJA 129th Independent Mixed Brigade, 5th Independent Tank Company, 23rd Independent AA Company, 80th Airfield Battalion and 6th Disembarkation Unit. During the Invasion of the Kuril Islands by the Soviet Union after the end of World War II, Japanese forces on Uruppu surrendered without resistance.