The relatively short time span from 1927, after the Nationalists’ creation of the Nanjing Government, to 1937, at the start of the Sino-Japanese war, makes it difficult to evaluate that government. Today, there are mixed views.
During a portion of that same time span, Japan tried to solidify their physical and international control of Manchuria. Protective and restive about their position, Japan sought to expand its empire further into China. That inevitably forced a confrontation with the Nationalist led Nanjing Government.