The second Sino-Japanese War was a major invasion of mainland China by Japan preceding and during World War II. It ended with the surrender of Japan in 1945. In Chinese, the war is known as the War to Resist the Japanese (抗日).
Overview
Most historians place the beginning of the second Sino-Japanese War on the Battle of Lugou Bridge (also known as the "Marco Polo Bridge Incident") on July 7, 1937. However, Chinese historians place the starting point at the Mukden Incident of September 18, 1931. Following the Mukden Incident, the Japanese Guandong army occupied Manchuria and established the puppet state of Manchukuo (February 1932). Japan pressured China into recognising the independence of Manchukuo. China and Japan did not formally declare war against each other until after the attack on Pearl Harbor on 7 December 1941.
Following the Battle of Lugou Bridge in 1937, the Japanese occupied Shanghai, Nanjing and Northern Shanxi as part of campaigns involving approximately 200,000 Japanese soldiers, and considerably more Chinese soldiers. After the fall of Nanjing, it is estimated that as many as 300,000 people died in the Nanjing Massacre.
While by 1940 Japan held most of the eastern coastal areas of China, guerrilla fighting continued in the conquered areas. The Nationalist government of Chiang Kai-shek struggled on from a provisional capital at Chongqing City; however, realizing that he also faced a threat from communist forces of Mao Zedong, he largely tried to preserve the strength of his army, avoiding heavy battle with the Japanese, in the hopes of defeating the Communists once the Japanese left. Moreover Chiang could not risk an all-out campaign given the well under-trained, equipped, organized Chinese armies and opposition against his leadership within and outside the Kuomintang.
Most military analysts predicted that the Chinese could not keep up the fighting with most of the war factories located in the prosperous areas either under or near Japanese control. Other global powers were reluctant to provide any support unless securing some clandestine purpose because in their opinion the Chinese would eventually lose the war. They expected any support given to China might worsen their own relationship with the Japanese, who taunted the Kuomintang with the prospect of conquest within 3 months.
Germany and the Soviet Union did provide support to the Chinese before the war escalated to the Asian theatre of World War II. The Soviet Union was exploiting the Kuomintang government to hinder the Japanese from invading Siberia, thus saving herself from a two-front war. Furthermore, the Soviets expected any major conflict between the Japanese and the Chinese to hamper any Kuomintang effort to remove the Communist Party of China (CCP) opposition or, in the best scenario, hoped to install a friendly Communist government surreptitiously after the dwindling of Kuomintang authority. Soviet technicians upgraded and handled some of the Chinese war-supply transport. Military supplies and advisors arrived - one Russian named Zhukov witnessed the battle of Tai er zhuang.
Because of Chiang Kai-shek's anti-communist policy and hopes of defeating the CCP, Germany provided the largest proportion of Chinese arms imports. German military advisors modernized and trained the Chinese armies; Chinese officers (including Chiang's second son) were educated in and served in the German army before World War II.
Nevertheless the proposed 30 new divisions equipped with all German arms did not materialize as the Germans sided with the Japanese later in World War II.
Other prominent powers, including the United States of America, Britain and France, only assisted in war supply contracts up to the attack on Pearl Harbor in late 1941, when major influx of trained military personnels and supplies boosted Chinese chance of keeping up the fighting.
Chiang Kai-shek received some supplies from the United States once the conflict was escalated to the Asian theatre of WWII, and he was appointed Commander-in-chief of the China war zone by the Allies in 1942. Notorious relationship between Colonel Joseph Stilwell and Chiang led to Stilwell's devious criticism and his minimizing of the Chinese contribution in World War II in the American media and to President Franklin Roosevelt. The Allies thus underestimated the Chinese need for supplies and trained personnels. Stilwell also incited power struggles within the Kuomintang which eventually contributed to the rise of the CCP.
Both sides fought to a stalemate after 1941, mainly owing to the dispersion of Japanese forces through vast areas of China - hence Japan could not concentrate its superior armor and firepower. Guerilla activities behind the frontlines also meant constantly deploying stationary Japanese forces in major cities and at road and rail junctions. Control over the countryside and villages gradually swung towards the CCP and Kuomintang.
Japan invaded the Pacific and Southeast Asia (1941) to secure more war supplies (especially the oil resources in Dutch East Indies) but ended up bringing the United States of America into the conflict. As Japanese position in the Pacific was deteriorating fast, a final effort to defeat the Chinese or at least forced any sort of agreements brought the Hubei, Henan, Guangxi provinces under Japanese administration. Nevertheless their prospect of tranferring their troops to fight the Americans was in vain and only committed the Guandong Army from Manchuria in their "Sho plan", which later facilitated the Soviet advancement after the war declaration on August 8 1945.
Japan capitulated to the allies on August 14, 1945. The Japanese troops in China formally surrendered on September 9, 1945 and by the provisions of the Cairo Conference of 1943 the lands of Manchuria, Taiwan and the Pescadores Islands reverted to China. However the Ryukyu islands have never regained their independence.
Casualties Assessment
The conflict lasted for 97 months and 3 days (measured from 1937 to 1945). The Kuomintang fought in 22 major engagements, each of which involved at least one hundred thousand troops from both sides, and in just over 40,000 skirmishes. The CCP fought in 111,500 engagements of various sizes. The Japanese recorded around 1.1 million military casualties, wounded and missing. The Chinese suffered much worse, losing approximately 3.22 million soldiers. 9.13 million civilians died in crossfire, and another 8.4 million as non-military casualties. Property loss of the Chinese worthed up to 383,301.3 million US dollars according to the currency exchange rate in July 1937, roughly 50 times of the GDP of Japan (770 million US dollars).