Japanese forces occupied large portions of the Empire of Korea during the Russo-Japanese War of 1904–1905, and a substantial was established in Seoul to protect the Japanese embassy and civilians on March 11, 1904. After the Annexation of Korea by the Empire of Japan in 1910, this force was renamed the "Chosen Chusatsugun", and was further renamed the Japanese Korean Army on June 1, 1918. The primary task of the Korean Army was to guard the Korean peninsula against possible incursions from the Soviet Union; however, its units were also used for suppression of nationalist uprisings and political dissent within Korea itself. The Korean Army also came to the assistance of the Kwantung Army in its unauthorized invasion of Manchuria in 1931. In 1941, the Army was subordinated to the General Defense Command.