Nice rare stamp. Manchukuo (Chinese: 满洲国; pinyin: Mǎnzhōuguó; literally "Manchu state") or Manshū-koku (Japanese: 満州国) was a puppet state in Manchuria and eastern Inner Mongolia, governed under a form of constitutional monarchy. The region was the historical homeland of the Manchus, who founded the Qing Empire in China. In 1931, the region was seized by Japan following the Mukden Incident and in 1932, a sympathetic government was established, with Puyi, the last Qing emperor, installed as the nominal regent and emperor. Manchukuo's government was abolished in 1945 after the defeat of Imperial Japan at the end of World War II. The territories formally claimed by the puppet state were first seized in the Soviet invasion of Manchuria in August 1945, and then formally transferred to Chinese administration in the following year.