The Kuomintang had earlier had an alliance with the Chinese Communist Party to fight against the warlords but turned against the CCP in 1927 mainly to get rid of the Communists, to protect his interests and to unite China under the KMT.

The KMT and CCP alliance broke down at Shanghai as Chiang Kai-shek felt that he no longer needed his communist partner, in fact he was afraid of the growing strength and support the CCP had. The CCP had gained popular support from the peasants and workers through the expedition by spreading propaganda messages and setting up of trade unions. The increase in support would then be a threat to the KMT's existence. Furthermore, the Communists ideas had made an impact even on the KMT members, therefore, in 1927 Chiang ordered the Shanghai Massacre to purge any Communist influence within his organisation and the Communists.

Another reason for turning...