Following the establishment of
Manchukuo, the
Kwantung Army launched an operation to secure its southern frontier with China by attacking and capturing
Shanhaiguan Pass at the
Great Wall on 3 January 1933. The province of
Rehe, on the northern side of the Great Wall, was the next target. Declaring the province to be historically a portion of
Manchuria, the Japanese Army initially hoped to secure it through the defection of General
Tang Yulin to the Manchukuo cause. When this failed, the military option was placed into action. Assigned to this operation were the Japanese
6th Division and
8th Division and
14th and
33rd Mixed Brigades of infantry,
4th Cavalry Brigade with
Type 92 Heavy Armored Cars, and the 1st Special Tank Company. The Japanese army's
chief of staff requested emperor
Hirohito's sanction for the "
strategic operation" against Chinese forces in Rehe. Hoping that it was the last of the army's operations in the area and that it would bring an end to the Manchurian matter, the Emperor approved, while stating explicitly that the army was not to go beyond China's Great Wall. The Chinese armies gathered to defend Rehe numbered between 100,000 and 150,000 with 40,000 of the Northeastern army under Wan Fulin, 30,000–50,000 under Tang Yulin and 30,000 former Guominjun under Sun Dianying and Song Zheyuan. Irregular forces included village militias, Manchurian bandits in exile and 5 volunteer brigades under Zhu Qinglan, though these volunteers rather than aiding the defense hindered it and Zhang Xueliang issued warrants for the arrest of the volunteers. ==The battle==