In 1919 when the Paris Peace Conference refused to abrogate foreign privileges, there was a spontaneous upsurge of Chinese nationalism and a huge uprising of students and urban workers. This provided a new contituency for Sun Yat-sen. In 1923, Sun reorganised his Nationalist (Kuomintang or KMT) Party and allied it to the Chinese Communist Party (CCP) and prepared to unite the country.

Sun died in 1925, and it was the Moscow trained general of the KMT army, Chaing Kai-shek, who led the great Northerm march of 1926 which aimed at the elimination of the warlords and unification of the country.

Helped by peasant and worker uprisings along the route, it was astonishingly successful, and by April 1927 Chiang had established his capital in Nanking.

But the uneasy alliance of KMT and CCP could not hold, and in 1927 Chiang turned on his allies, massacring the communists in Shanghai. Furthermore, the warlords were not entirely eliminated, and Chiang's rule was effectively limited to the lower Yangze (southern China)