On March 12, 1925, the Chinese nationalist leader Sun Yat-Sen died of cancer in a Beijing hospital. Dedicated to the cause of revolution and a democratic, unified China, Sun had led the popular revolt against the imperial government that ruled the nation; he founded the Kuomintang, or National People’s Party, following the fall of the last emperor of the Manchu dynasty in 1911. The Kuomintang included several political factions as well as a military arm, later modeled on the army of the Soviet Union. Despite Sun's attempts to unify the country, central government remained weak and China was divided by rivalries between local warlords and governments established in the major cities, including Shanghai and Beijing.

After Sun’s death, the Kuomintang split into rival factions led by Chiang Kai-Shek and Wang Jingwei. In 1927, the Chinese Communist party left the Kuomintang, an event that led to nearly twenty years of civil war between the Kuomintang and the Communist forces, led in the 1930s by Mao Tse-Tung. Both sides claimed Sun Yat-Sen as a founder and historic figurehead; the struggle was not resolved until the Communist seizure of power in Beijing and the establishment of the People’s Republic of China in 1949. Exiled to the island of Taiwan, the Kuomintang set up a new republican government on the island, which the People's Republic still claims as a province of China under the authority of the Beijing government.

When Sun Yat-Sen died in 1925, China was in the midst of fairly serious upheaval.  Chinese were very unhappy with the way in which their country was dominated by foreign powers and were pushing for greater autonomy and independence.

This push was also the cause of strife within China.  There were two leading nationalist groups that were trying to create a united (not divided among warlords) and independent (without the sort of unequal treaties that gave Western countries and the Japanese so much power) China.  These were the KMT and the Communist Party.  When Sun died, they were on the verge of splitting.  Their split led to a civil war that lasted until the Communists won in 1949.