 Allied army support was given to Admiral Kolchak's White government at Omsk, while the Japanese continued to support Kolchak's rivals in Grigory Semyonov and Ivan Kalmykov.In the summer of 1919, the White regime in Siberia collapsed, after the capture and execution of Admiral Kolchak by the Red Army.In June 1920, the Americans, British and the remaining allied coalition partners withdrew from Vladivostok.