The July 7th Incident (also known as the "Lugou" or "Marco Polo" Bridge Incident) marked the beginning of the nationwide resistance.

In February 1936, following the formal establishment of a fascist regime in Japan, the war of aggression against China began to pick up pace.

On the night of July 7, 1937, a unit of the Japanese China Garrison Army at Fengtai, Beiping (the name used at the time for Beijing), staged a provocative maneuver near the Lugou Bridge. Around midnight, the Japanese demanded entry to the town of Wanping to search for one of their soldiers whom they claimed to have gone missing during the maneuver. After the Chinese side rejected their demand, the Japanese launched an attack on the defending Chinese troops and bombarded the town. This incident marked the start of Japan's full-scale war of aggression against China. A unit of the Chinese 29th Army, charged with the defense of Wanping, was forced to fight back in a struggle that was to mark the beginning of China's nationwide War of Resistance.