Chongqing is a municipality in Southwestern China. Chongqing is one of the four direct-administered municipalities under the Central People's Government, along with Beijing, Shanghai, and Tianjin. It is the only directly administrated municipality located deep inland. The municipality covers a large geographical area roughly the size of Austria, which includes several disjunct urban areas in addition to Chongqing proper. Due to its classification, the municipality of Chongqing is the largest city proper in the world by area, though it does not have the largest urban area.

The Second Sino-Japanese War was the war fought between the Republic of China and the Empire of Japan from 1937 to 1945 as part of World War II. It is often regarded as the beginning of World War II in Asia. It was the largest Asian war in the 20th century and has been described as "the Asian Holocaust", in reference to the scale of Japanese war crimes against Chinese civilians. It is known in Japan as the Second China–Japan War, and in China as the Chinese War of Resistance against Japanese Aggression.