The Empire of China (AD 1915–1916) proclaimed by Yuan Shikai sparked the National Protection War, resulting in the premature collapse of the regime 101 days later. The Manchu Restoration (AD 1917) was an unsuccessful attempt at reviving the Qing dynasty, lasting merely 11 days. Similarly, the Manchukuo (AD 1932–1945; monarchy since AD 1934), a puppet state of the Empire of Japan during World War II with limited diplomatic recognition, is not regarded as a legitimate regime. Ergo, historians usually consider the abdication of the Xuantong Emperor on 12 February 1912 as the end of the Chinese dynastic system. Dynastic rule in China lasted almost four millennia.