The Warlord Era (simplified Chinese: 军阀时代; traditional Chinese: 軍閥時代; pinyin: Jūnfá shídài, 1916–1928) was a period in the history of the Republic of China when the control of the country was divided among its military cliques in the mainland regions of Sichuan, Shanxi, Qinghai, Ningxia, Guangdong, Guangxi, Gansu, Yunnan and Xinjiang.
The era lasted from the death of Yuan Shikai in 1916 until 1928 (with the conclusion of the Northern Expedition with the Northeast Flag Replacement, the beginning of the "Nanjing decade"). However, when old warlords, such as Wu Peifu and Sun Chuanfang, were deposed, new minor warlords persisted into the 1930s and 1940s, as the central government struggled to keep its allies under rein, a great problem for the Kuomintang (KMT) through World War II and after during the Chinese Civil War. Some of the most notable warlord wars, post-1928, including the Central Plains War, involved nearly a million soldiers. The division of the country continued after the Warlord Era until the fall of the Nationalist government at the end of the civil war.
The origins of the armies and leaders which dominated politics after 1912 lie in the military reforms of the late Qing dynasty. These did not establish a national army but utilized regional armies and militias which lacked standardization or consistency. During the later phrase of the Taiping Rebellion (1850–1864), provincial governors were allowed to raise their own armies to fight against the Taipings, which were not disbanded when the war finally ended in 1864 with the sack of Nanking. The most powerful regional army was the northern-based Beiyang Army under Yuan Shikai, which received the best in training and modern weaponry. Officers were loyal to their superiors and formed cliques based upon geography and shared academy experiences. Units were composed of men from the same province. This policy was meant to reduce dialectal miscommunication and encourage regionalistic tendencies.