The Kuomintang (KMT), led by Sun Yat-sen, created a new government in Guangzhou to rival the warlords who ruled over large swathes of China and prevented the formation of a solid central government. After Sun's efforts to obtain aid from Western countries were ignored, he turned to the Soviet Union. In 1923, Sun and Soviet representative Adolph Joffe in Shanghai pledged Soviet assistance to China's unification in the Sun–Joffe Manifesto, a declaration of cooperation among the Comintern, KMT, and CCP. Comintern agent Mikhail Borodin arrived in 1923 to aid in the reorganization and consolidation of both the CCP and the KMT along the lines of the Communist Party of the Soviet Union. The CCP, which was initially a study group, and the KMT jointly formed the First United Front.

In 1923, Sun sent Chiang Kai-shek, one of his lieutenants, for several months of military and political study in Moscow. Chiang then became the head of the Whampoa Military Academy that trained the next generation of military leaders. The Soviets provided the academy with teaching material, organization, and equipment, including munitions. They also provided education in many of the techniques for mass mobilization. With this aid, Sun raised a dedicated "army of the party," with which he hoped to defeat the warlords militarily. CCP members were also present in the academy, and many of them became instructors, including Zhou Enlai, who was made a political instructor.

Communist members were allowed to join the KMT on an individual basis. The CCP itself was still small at the time, having a membership of 300 in 1922 and only 1,500 by 1925. As of 1923, the KMT had 50,000 members.