The Northern Expedition
After the first KMT-CPC cooperation was established, the CPC Central Committee decided in February 1926 that the Party's main task at the time was to move the revolutionary forces northward from coastal Guangdong Province. The following summer the KMT and the CPC decided to launch the Northern Expedition and wage a war against three notorious Northern Warlords – Wu Peifu, Sun Chuanfang (1885-1935) and Zhang Zuolin (1875-1928) – who were backed by the imperialists.
On July 9, the 100,000-strong National Revolutionary Army under the Guangzhou-based National Government launched the Northern Expedition. With widespread support, the revolutionary forces spread rapidly. They took Wuchang, a city in Hubei Province, on October 10 and defeated Wu Peifu's main forces. They seized Jiujiang and Nanchang, two cities in Jiangxi Province, in November and wiped out the main forces of Sun Chuanfang. A succession of warlords in Fujian, Zhejiang and other provinces surrendered.
The Northern Expedition was proposed by the CPC and launched as a movement against warlords and occupying imperialists. In the course of the expedition, the Chinese Communists made enormous contributions both by conducting political work in the army and mobilizing the workers and peasants.
Under the command of Ye Ting (1896-1946), a Communist and a prestigious general, the Independent Regiment, composing mainly of CPC members, served as the vanguard in the Fourth Army which was renowned as "Iron Troops."
However, at a critical moment of the Northern Expedition, Chiang Kai-shek, Wang Jingwei and other KMT right-wingers launched counter-revolutionary coups in Shanghai and Wuhan. Due to Chen Duxiu's Right opportunist errors, the CPC didn't take prompt actions to deal with such a sudden incident. As a result, Chiang Kai-shek seized control of the KMT and established his rule as a new warlord. The Northern Expedition thus ended in failure.
北伐戰爭
第一次國共合作建立后，1926年2月，中共中央明確指出黨在目前的主要任務是推動廣東革命勢力向北發展。1926年夏，國共兩黨決定進行北伐戰爭，其直接打擊目標是受帝國主義支持的北洋軍閥吳佩孚、孫傳芳、張作霖三派勢力。7月9日，廣東國民政府領導的國民革命軍10萬人正式出師北伐。在各界民眾的支持下，北伐軍高歌猛進，于10月10日攻占湖北武昌，全殲軍閥吳佩孚部主力；11月占領江西九江、南昌，并一舉殲滅軍閥孫傳芳部主力。福建、浙江等省的軍閥也紛紛倒向北伐軍。
北伐戰爭是在中國共產黨提出的反對帝國主義、反對封建軍閥的口號下進行的。在北伐過程中，中國共產黨人在軍隊、政治工作以及發動工農群眾方面作出了巨大貢獻。共產黨員葉挺領導的、以共產黨員為骨干組成的第四軍獨立團，成為贏得“鐵軍”稱號的第四軍中的一支英勇善戰的先鋒部隊，葉挺也被譽為北伐名將。但是，正當北伐軍向前發展的緊要關頭，蔣介石、汪精衛等國民黨右派勢力先后在上海和武漢發動反革命政變。同時，因受陳獨秀右傾機會主義錯誤的影響，中國共產黨未能及時采取應付突發事變的正確措施。結果，蔣介石反動集團竊取了革命果實，建立了新的軍閥統治，轟轟烈烈的北伐戰爭以失敗告終。
