Peng enlisted as a private second class soldier, with a monthly wage of 5.5 yuan, 2 yuan of which he sent back to support his family. Within seven months, he was promoted to private first class, with a monthly wage of 6 yuan, 3 yuan of which he sent to his family. One of Peng's commanding officers was an idealistic Nationalist who had participated in the 1911 Xinhai Revolution and influenced Peng to sympathize with the Kuomintang's goals of social reform and national reunification. Afger another civil war broke out in 1917, Peng's regiment split from the rest of its army and joined the forces of Tang Shengzhi, who was aligned with Tan Yankai and Sun Yat-sen against those aligned with the northern warlord Wu Peifu. Peng received training in formal tactics from an officer in his brigade. In July 1918, Peng was captured on a reconnaissance mission behind enemy lines, but he was released after two weeks. In April 1919, Peng was promoted to master sergeant and acting platoon commander. Tang Shengzhi's forces drove enemy troops out of Hunan in July 1920 and captured the provincial capital of Changsha.