Soviet soldiers at a New Year costume party on Dec. 31, 1938. The sign reads: “Samurai will remember it for a long time.” In July-Aug. 1938, Soviet and Japanese forces clashed in the Battle of Lake Khasan at the juncture of Soviet, Korean and Manchurian borders.

Soviet soldiers at a New Year costume party on Dec. 31, 1938. The sign reads: “Samurai will remember it for a long time.” In July-Aug. 1938, Soviet and Japanese forces clashed in the Battle of Lake Khasan at the juncture of Soviet, Korean and Manchurian borders.