Shanghai War of 1932

January 28 Incident
The Chinese 19th Route Army in a defensive position.
Date January 28 – March 3, 1932 Location In and around Shanghai, China Result Ceasefire; Shanghai demilitarized
Belligerents
China	Japan
Commanders and leaders
19th Route Army: Jiang Guangnai Cai Tingkai 5th Army: Zhang Zhizhong	Commander: Yoshinori Shirakawa Chief of staff: Kanichiro Tashiro
Units involved
19th Route Army 5th Army	Shanghai Expeditionary Army  Imperial Japanese Navy
Strength
50,000	100,000+ 80 ships 300 airplanes
Casualties and losses
13,000, including 4,000 KIA	5,000, including 3,000+ KIA

The January 28 Incident or Shanghai Incident (January 28 – March 3, 1932) was a conflict between the Republic of China and the Empire of Japan, before official hostilities of the Second Sino-Japanese War commenced in 1937.

In Chinese literature it is known as the January 28 Incident (simplified Chinese: 一·二八事变; traditional Chinese: 一·二八事變; pinyin: Yī Èrbā Shìbiàn), while in Western sources it is often called the Shanghai War of 1932 or the Shanghai Incident. In Japan it is known as the First Shanghai Incident, alluding to the Second Shanghai Incident, which is the Japanese name for the Battle of Shanghai that occurred during the opening stages of the Second Sino-Japanese War in 1937.

After the Mukden Incident, Japan had acquired the vast northeastern region of China and would eventually establish the puppet government of Manchukuo. However, the Japanese military planned to increase Japanese influence further, especially into Shanghai where Japan, along with the various western powers, had extraterritorial concessions.

In order to provide a casus belli to justify further military action in China, the Japanese military instigated seemingly anti-Japanese incidents. On January 18, five Japanese Buddhist monks, members of an ardently nationalist sect, were beaten near Shanghai's Sanyou Factory (simplified Chinese: 三友实业社; traditional Chinese: 三友實業社; pinyin: Sānyǒu Shíyèshè) by agitated Chinese civilians. Two were seriously injured, and one died. Over the next few hours, a group burnt down the factory (sources argue this was orchestrated by Japanese agents, though it might have been carried out by Chinese in response to the Shanghai Municipal Police's aggressive anti-riot tactics in the aftermath of the beating of the monks).

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