The leader of the Chinese Nationalist Party, also known as the Kuomintang (KMT), during the Chinese Civil War was Chiang Kai-shek. After Sun Yat-sen's death, Chiang emerged as the party's prominent figure, advocating for a unified and modern China. He led the KMT in the Northern Expedition to defeat warlords and establish a central government. However, Chiang's focus on fighting the Communist Party led to a protracted civil war. His regime faced internal strife, corruption, and eventually significant opposition from Communist forces led by Mao Zedong, culminating in the Nationalists’ retreat to Taiwan in 1949 after their defeat in the civil war.