The assault on Nanking occurred during the Second Sino-Japanese War, which began in July 1937. As Japanese forces advanced into Chinese territory, Nanking, the capital of the Republic of China, became a primary target due to its strategic importance. Following months of intense fighting, Japanese troops, led by Lieutenant General Yasuhiko Asaka, launched a coordinated attack on December 9, 1937, aimed at seizing control of the city. The Imperial Japanese Army had been planning this operation, seeking to leverage their military superiority and disrupt the Chinese government's efforts to rally national defense forces.

Initial resistance from the Chinese Nationalist troops, under the command of General Zhang Zizhong, aimed to defend the city; however, the overwhelming firepower and tactical maneuvers of the Japanese forces soon overwhelmed them. The battle unfolded with fierce combat, resulting in heavy casualties on both sides. Nanking's defenses crumbled swiftly, and Japanese troops began to infiltrate the city.

The fall of Nanking would lead to one of the most notorious episodes of the war, known as the Nanking Massacre, where civilian atrocities and war crimes were reported. The occupation solidified Japanese control over eastern China and marked a turning point in the Sino-Japanese conflict, establishing a brutal precedent for warfare and occupation in the region.