Sun Yat-sen (sōōn yät-sĕn), Mandarin Sun Wen, 1866–1925, Chinese revolutionary. He was born near Guangzhou into a farm-owning family. He attended (1879–82) an Anglican boys school in Honolulu, where he came under Western influence, particularly that of Christianity. In 1892 he received a diploma from a Hong Kong medical school, and he subsequently practiced medicine in that city. Thereafter all his activities were devoted to overthrowing the Ch'ing dynasty and establishing a stable Chinese republic.
Sun fled China in 1895, after an abortive revolt, and then toured the world several times to enlist the aid of overseas Chinese in financing his activities. In that period he made an intensive study of Western political and social theory and was deeply impressed with the writings of Karl Marx and Henry George. Sun organized (1905) a revolutionary league, the T'ung Meng Hui, in Japan and gradually perfected his political conceptions, which were based on the Three People's Principles: nationalism, democracy, and the people's livelihood. Revolution erupted in China, and Sun was elected provisional president of the Chinese republic in Dec., 1911, but two months later he resigned in favor of Yüan Shih-kai. Later, when Sung Chiao-jen transformed the T'ung Meng Hui into a federated political party called the Kuomintang, Sun served as its director.
Meanwhile, opposition developed to Yüan's dictatorial methods; in 1913 Sun led an unsuccessful revolt against Yüan, and he was forced to seek asylum in Japan, where he reorganized the Kuomintang. He returned to China in 1917, and in 1921 he was elected president of a self-proclaimed national government at Guangzhou in S China. To develop the military power needed for the Northern Expedition against the militarists at Beijing, he established the Whampoa Military Academy (now Huangpu Military Academy), with Chiang Kai-shek as its commandant and with such party leaders as Wang Ching-wei and Hu Han-min as political instructors. In 1924, to hasten the conquest of China, he began a policy of active cooperation with the Chinese Communists and he accepted the help of the USSR in reorganizing the Kuomintang.
After Sun's death, when the Communists and the Kuomintang split (1927), each group claimed to be his true heirs. The official veneration of Sun's memory (especially in the Kuomintang) was a virtual cult, which centered around his tomb in Nanjing. His widow, the former Soong Ch'ing-ling (see Soong, family), whom he married in 1914, rose to a high position in the government of Communist China. He wrote San Min Chu I (tr. 1928), Memoirs of a Chinese Revolutionary (1927, repr. 1970), and Fundamentals of National Reconstruction (tr. 1953).
See biographies by L. Sharman (1934) and B. D. Martin (1952); L. S. Hsu, Sun Yat-sen, His Political and Social Ideals: A Sourcebook (1933); S. C. Leng and N. D. Palmer, Sun Yat-sen and Communism (1960); H. Z. Schiffrin, Sun Yat-sen and the Origins of the Chinese Revolution (1970); M. Wilbur, Sun Yat-sen (1977).