The Second Sino-Japanese War was a military conflict that was primarily waged between the Republic of China and the Empire of Japan. The war made up the Chinese theater of the wider Pacific Theater of the Second World War. The beginning of the war is conventionally dated to the Marco Polo Bridge Incident on 7 July 1937, when a dispute between Japanese and Chinese troops in Peking escalated into a full-scale invasion. This full-scale war between the Chinese and the Empire of Japan is often regarded as the beginning of World War II in Asia. In 2017 the Ministry of Education in the People's Republic of China decreed that the term "eight-year war" in all textbooks should be replaced by "fourteen-year war", with a revised starting date of 18 September 1931 provided by the Japanese invasion of Manchuria. According to historian Rana Mitter, historians in China are unhappy with the blanket revision, and the Republic of China did not consider itself to be continuously at war with Japan over these six years.