Second Sino-Japanese War

The Second Sino-Japanese War was fought from 1937 to 1945 between the Republic of China and the Empire of Japan, growing out of decades of Japanese expansion into Chinese territory and merging into the wider Pacific theater of World War II after the 1941 attack on Pearl Harbor. The war began in earnest with the Marco Polo Bridge Incident near Beijing in July 1937, followed by rapid Japanese advances that captured Shanghai, the Chinese capital Nanjing, where occupying forces perpetrated the mass atrocity known as the Nanjing Massacre, and much of eastern China by 1938. Chinese resistance, divided between the Nationalist government under Chiang Kai-shek and the Chinese Communist Party under Mao Zedong in an uneasy united front, fought a grinding war of attrition that tied down large Japanese forces for years even as front lines stabilized. Japan's surrender in August 1945, following the atomic bombings of Hiroshima and Nagasaki and the Soviet declaration of war, ended the conflict, but China's civil war between the Nationalists and Communists, only briefly suspended for the united front, resumed almost immediately afterward.