January 31 Incident

Following the death of Zhang Zuolin, Japan acquired the vast northeastern region of China and would eventually establish the puppet government of Manchukuo. However, the Japanese military was not satisfied and planned to increase Japanese influence further, especially into Shanghai where it had concessions. In order to achieve this, the Japanese needed to create incidents to provide some pretexts justifying further military action in China. On January 21, 1932, five Japanese monks were beaten near the Sanyou Factory by agitated Chinese civilians. Meanwhile, some instigated Japanese men burnt down the factory and killed one and hurt several police officers sent by the Chinese authorities. This caused an upsurge of anti-Japanese protests against Japanese presence in the city and its concessions, as residents of Shanghai marched onto the streets. They also called for boycott of Japanese goods.

The situation by this time could break out into mass rioting. By January 30, the Japanese military had already concentrated around thirty ships, forty airplanes, and nearly seven thousand troops around the shoreline of Shanghai, to put down any resistance in case violence broke out with the justification it had to defend its own concessions. The Japanese also issued an ultimatum to the Shanghai municipal government, demanding a public condemnation and monetary compensation by the Chinese for any Japanese interest damaged in the monk incident, and that the Chinese government actively put down all anti-Japanese protests in the city. In the afternoon of January 31, the Shanghai municipal government agreed to these demands. However, around midnight, three thousand Japanese troops proceeded to attack various targets, such as train stations, around the city. The Chinese 19th Route Army put up a fierce resistance and the Japanese hastily retreated. Chiang Kai-shek also sent his 5th Army, including his elite 87th and 88th divisions, into the fray. Thus the Battle of Shanghai began.

Because Shanghai was a metropolitan city with many foreign interests invested in it, other countries, such as the United States and Great Britain, attempted to negotiate with Japan right from the start for a ceasefire. However, Japan refused and continued to mobilize more and more troops into the region around Shanghai to fight the Chinese defenders. On January 15, American, British, and French representatives brokered a half-day respite for humanitarian relief to civilians caught in the crossfire. On February 15, the Japanese issued another ultimatum, demanding that the Chinese retreat twenty kilometers from the Shanghai foreign concession border, which was promptly refused by the Chinese forces. This only intensified fighting in the city. The Japanese were still not able to take the city and by the middle of February their number was increased to nearly ninety thousand, supported by eighty warships and three hundred airplanes. Japanese bombardments also increased to force the Chinese away from their defensive positions, while commercial and residential districts were torched for the same purpose. The Chinese positions deteriorated rapidly as they were without naval and armored support, and their numbers dwindled to fewer than fifty thousand, while the Japanese had a hundred thousand troops supported by aerial and naval bombardment.

On March 5, the 19th Route Army issued a telegram stating that they had to pull out of Shanghai because of lack of supplies and manpower. The next day, the 19th Route Army and the 5th Army retreated from Shanghai, marking the official end of the battle.

SOURCE: Wikipedia