The Second Sino-Japanese War was fought between the Republic of China and the Empire of Japan and its puppet states between 1937 and 1945, following a period of conflict localized to Manchuria that started in 1931. It is often regarded as the beginning of World War II in Asia, as the wars became heavily intertwined after Japan attacked the United States. It was the largest Asian war in the 20th century. On 18 September 1931, the Japanese staged the Mukden incident, a false flag event fabricated to justify their invasion of Manchuria and establishment of the puppet state of Manchukuo. This is sometimes marked as the beginning of the war. From 1931 to 1937, China and Japan engaged in skirmishes, including in Shanghai and in Northern China. Nationalist and Chinese Communist Party (CCP) forces, respectively led by Chiang Kai-shek and Mao Zedong, had fought each other in the Chinese Civil War since 1927. In late 1933, Chiang Kai-shek encircled the Chinese Communists in an attempt to finally destroy them, forcing the Communists into the Long March, resulting in the Communists losing around 90% of their men. As a Japanese invasion became imminent, Chiang eventually formed a United Front with the Communists in 1936, a process that was hastened by the Xi'an Incident. The war is considered to have begun on 7 July 1937 after the Marco Polo Bridge incident near Beijing, which escalated into full-scale Japanese invasion of the rest of China. Following the protracted Battle of Shanghai, the Japanese captured the capital of Nanjing in 1937 and perpetrated the Nanjing Massacre. After failing to stop the Japanese capture of Wuhan in 1938, China's de facto capital at the time, the Nationalist government relocated to Chongqing in the Chinese interior. After the Sino-Soviet Non-Aggression Pact, Soviet aid bolstered the National Revolutionary Army and Air Force. By 1939, after Chinese victories at Changsha and with Japan's lines of communication stretched deep into the interior, the war reached a stalemate. The Japanese were unable to defeat CCP forces in Shaanxi, who waged a campaign of sabotage and guerrilla warfare. In November 1939, Nationalist forces launched a large scale winter offensive, and in August 1940, CCP forces launched the Hundred Regiments Offensive in central China. In retaliation, Japanese forces implemented massive scorched earth policies in North and Central China, killing millions of civilians. In April 1941, Soviet aid was halted with the Soviet–Japanese Neutrality Pact. In December 1941, Japan launched a surprise attack on Pearl Harbor and declared war on the United States and the United Kingdom. The US increased its aid to China under the Lend-Lease Act, becoming its main financial and military supporter. The British Empire supported the Chinese forces against Japan by sending supplies through the Burma Road, linking British colonies in India and Burma to China. Chinese forces also fought with British Empire forces against the Japanese in the Burma campaign to restore Allied usage after the Japanese occupied most of the Burma Road. With Burma cut off, the United States Army Air Forces airlifted material over the Himalayas. In 1944, Japan launched Operation Ichi-Go, the invasion of Henan and Changsha. In 1945, the Chinese Expeditionary Force resumed its advance in Burma and completed the Ledo Road linking India to China. China launched large counteroffensives in South China, repulsed a failed Japanese invasion of West Hunan, and recaptured Japanese occupied regions of Guangxi. Japan formally surrendered on 2 September 1945, following the atomic bombings of Hiroshima and Nagasaki, Soviet declaration of war and subsequent invasion of Manchuria, Inner Mongolia and Korea. The war resulted in the deaths of around 20 million people, mostly Chinese civilians. Japan carried out the largest attacks in the history of biological warfare, causing at least 200,000 deaths, and used chemical weapons including lethal blister agents. China was recognized as one of the Big Four Allied powers in World War II and one of the "Four Policemen", which formed the foundation of the United Nations. It regained Taiwan and became one of the five permanent members of the United Nations Security Council. The Chinese Civil War resumed in 1946, ending with a communist victory and the Proclamation of the People's Republic of China in 1949, while the government of the Republic of China relocated to Taiwan.
Names
=== Chinese === In both China's Mainland and Taiwan, the war is most commonly known as the "War of Resistance against Japanese Aggression" (simplified Chinese: 抗日战争; traditional Chinese: 抗日戰爭), and the name of it is usually shortened to "Resistance against Japanese Aggression" (抗日) or the "War of Resistance" (抗战; 抗戰). The countries also use the term "Eight Years' War of Resistance" (八年抗战; 八年抗戰), a traditional view which dates the war's beginning to the Marco Polo Bridge incident in 1937. Since 2017, the Chinese Communist Party's official view of Chinese historiography has held the 18 September 1931 Japanese invasion of Manchuria as the start of the" Fourteen Years' War of Resistance" (十四年抗战; 十四年抗戰). The 1931–1937 period is viewed as the "partial" war, which includes the "Northeast War of Resistance" (东北抗战), while 1937–1945 is viewed as a period of "total" war. This view of a fourteen-year war has political significance because it provides more recognition, internationally as China claims it fought the earliest and longest in a global war, and domestically for the role of northeast China in the War of Resistance. The CCP officially calls the conflict as "Chinese People's War of Resistance against Japanese Aggression" (Chinese: 中国人民抗日战争), while referring to it as part of the "World Anti-Fascist War", an alternate definition of World War II.
=== Japanese === In contemporary Japan, the name "Japan–China War" (Japanese: 日中戦争, romanized: Nitchū Sensō) is most commonly used because of its perceived objectivity. Dating the beginning of the war may also vary in Japanese context, with one Japanese historiographical view regarding the war as a "Fifteen-Year War" (Jyugonen Sensô), covering the period beginning with the invasion of Manchuria through the atomic bombings, and including both the war in China and the Pacific war. When the invasion of China proper began in earnest in July 1937 near Beijing, the Empire of Japan used "The North China Incident" (北支事變/華北事變, Hokushi Jihen/Kahoku Jihen), and with the outbreak of the Battle of Shanghai the following month, it was changed to "The China Incident" (支那事變, Shina Jihen). The word "incident" (事變, jihen) was used by Japan, as neither country had made a formal declaration of war at the outbreak of hostility. From the Japanese perspective, localizing these conflicts was beneficial in preventing intervention from other countries, particularly the United Kingdom and the United States, which were its primary source of petroleum and steel respectively. A formal expression of these conflicts would potentially lead to an American embargo in accordance with the Neutrality Acts of the 1930s. In addition, due to China's fractured political status, Japan often claimed that China was no longer a recognizable political entity on which war could be declared. In Japanese propaganda, the invasion of China became a holy war (聖戦, seisen), the first step of the "eight corners of the world under one roof" slogan (八紘一宇, Hakkō ichiu). In 1940, Japanese prime minister Fumimaro Konoe launched the Taisei Yokusankai. When both sides formally declared war in December 1941, the name was replaced by "Greater East Asia War" (大東亞戰爭, Daitōa Sensō). Although the Japanese government still uses the term "China Incident" in formal documents, the word Shina is considered derogatory by China and therefore the media in Japan often paraphrase with other expressions like "The Japan–China Incident" (日華事變/日支事變, Nikka Jiken/Nisshi Jiken), which were used by media as early as the 1930s. The name "Second Sino-Japanese War" is not commonly used in Japan as the China it fought a war against in 1894 to 1895 was led by the Qing dynasty, and thus is called the Qing-Japanese War (日清戦争, Nisshin–Sensō), rather than the First Sino-Japanese War.
Background
Japanese expansion
The First Sino-Japanese War (1894–1895) concluded with the defeat of China, then under the rule of the Qing dynasty, by Japan. Under the Treaty of Shimonoseki, China was forced to cede Taiwan and recognize the full and complete independence of Korea. Japan also annexed the Senkaku Islands, which Japan claims were uninhabited, in early 1895 as a result of its victory at the end of the war. Japan had also attempted to annex the Liaodong Peninsula following the war, though was forced to return it to China following the Triple Intervention by France, Germany, and Russia. In 1905, Japan defeated the Russian Empire in the Russo-Japanese War, gaining Dalian and southern Sakhalin and establishing a protectorate over Korea. In 1915, Japan issued the Twenty-One Demands to extort further political and commercial privilege from China, which was accepted by the regime of Yuan Shikai. Following World War I, Japan acquired the German Empire's sphere of influence in Shandong province, leading to nationwide anti-Japanese protests and mass demonstrations in China.
Warlord Era
The Qing dynasty was on the brink of collapse due to internal revolts and the imposition of the unequal treaties, while Japan had emerged as a great power through its efforts to modernize. In 1911, factions of the Qing Army uprose against the government, staging a revolution that swept across China's southern provinces. The Qing responded by appointing Yuan Shikai, commander of the loyalist Beiyang Army, as temporary prime minister in order to subdue the revolution. Yuan, wanting to remain in power, compromised with the revolutionaries, and agreed to abolish the monarchy and establish a new republican government, under the condition he be appointed president of China. The new Beiyang government of China was proclaimed in March 1912, after which Yuan Shikai began to amass power for himself. In 1913, the parliamentary political leader Song Jiaoren was assassinated; it is generally believed Yuan Shikai ordered the assassination. Yuan Shikai then forced the parliament to pass a bill to strengthen the power of the president and sought to restore the imperial system, becoming the new emperor of China. However, there was little support for an imperial restoration among the general population, and protests and demonstrations soon broke out across the country. Yuan's attempts at restoring the monarchy triggered the National Protection War, and Yuan Shikai was overthrown after only a few months. In the aftermath of Shikai's death in June 1916, control of China fell into the hands of the Beiyang Army leadership. The Beiyang government was a civilian government in name, but in practice it was a military dictatorship with a different warlord controlling each province of the country. China was reduced to a fractured state. As a result, China's prosperity began to wither and its economy declined. The country remained fragmented under the Beiyang Government and was unable to resist foreign incursions. This instability presented an opportunity for nationalistic politicians in Japan to press for territorial expansion.
Nationalist reunification
For the purpose of unifying China and defeating the regional warlords, the Kuomintang (KMT) in Guangzhou launched the Northern Expedition from 1926 to 1928 with limited assistance from the Soviet Union. The National Revolutionary Army (NRA) formed by the Kuomintang swept through southern and central China until it was checked in Shandong, where confrontations with the Japanese garrison escalated into armed conflict. The conflicts were collectively known as the Jinan incident of 1928, during which time the Japanese military killed several Chinese officials and fired artillery shells into Jinan. According to the investigation results of the Association of the Families of the Victims of the Jinan massacre, it showed that 6,123 Chinese civilians were killed and 1,701 injured. Relations between the Chinese Nationalist government and Japan severely worsened as a result of the Jinan incident. Zhang Zuolin and his Fengtian clique, despite being supported by Japan, failed to defend against the National Revolutionary Army approaching Beijing. Zhang Zuolin decided to retreat back to Manchuria, where he was assassinated by the Kwantung Army in 1928. His son, Zhang Xueliang, took over as the leader of the Fengtian clique in Manchuria. Later in the same year, Zhang declared his allegiance to the Nationalist government in Nanjing under Chiang Kai-shek, and consequently, China was nominally reunified under one government.
Start of the Chinese Civil War
In 1930, the Central Plains War broke out across China, involving regional commanders who had fought in alliance with the Kuomintang during the Northern Expedition, and the Nanjing government under Chiang. The Chinese Communist Party (CCP) previously fought openly against the Nanjing government after the Shanghai massacre of 1927, and they continued to expand during this protracted civil war. The Kuomintang government focused its efforts on suppressing the Chinese Communists instead of opposing the Japanese. Chiang Kai-shek reasoned that only a unified command could resist foreign powers, leading to his defensive policy of "first internal pacification, then external resistance" (Chinese: 攘外必先安內), through its encirclement campaigns against the Communists. Following the 1931 Mukden Incident, Nationalist planners identified critical vulnerabilities in the Kuomintang's urban-centric economic base, particularly the concentration of heavy industry in vulnerable coastal cities. Chiang Kai-shek’s policy of 'internal pacification' was not just a military campaign against the communists, but also a major economic reorganization project. Recognizing that China lacked the industrial base for a localized total war in 1930, the Nationalist government sought to consolidate the southwestern interior as a strategic base while attempting to modernize the national currency and military before a full-scale confrontation with Japan became inevitable. To address these weaknesses, the central government initiated projects to modernize and solidify the Kuomintang's control over the national currency and industrial structure, while planning for the eventual redistribution of factories and arsenals to the interior. Nationalist forces prioritized the destruction of Communist soviets, driving the CCP out of their enclaves and onto the Long March to Yan'an by 1934. On 1 August 1935, the Communist Party issued the August First Declaration. It called for the creation of a United Front of all Chinese parties, organizations, and people of all circles, including overseas Chinese and ethnic minorities, to oppose the Japanese. A December 1936 kidnapping by two Nationalist Generals, the Xi'an Incident, forced Chiang Kai-shek to hasten negotiations for a United Front with the Chinese Communists to oppose Japan, a process finalized at the outbreak of war.
Pre-war events
Invasion of Manchuria
The chronic warfare in China provided excellent opportunities for Japan, which saw Manchuria as a limitless supply of raw materials, a market for its manufactured goods (now excluded from the markets of many Western countries as a result of Depression-era tariffs), and a protective buffer state against the Soviet Union in Siberia. As a result, the Japanese Army was widely prevalent in Manchuria immediately following the Japanese victory in the Russo-Japanese War in 1905, where Japan gained control over the South Manchuria Railway Zone and the Kwantung Leased Territory in Manchuria. As a result of their strengthened position, by 1915 Japan had negotiated a significant amount of economic privilege in the region by pressuring Yuan Shikai, the president of the Republic of China at the time. With a widened range of economic privileges in Manchuria, Japan began focusing on developing and protecting matters of economic interests. This included railroads, businesses, natural resources, and a general control of the territory. The Japanese Kwantung Army was established in 1919 to protect these interests. Both the 1921 and 1927 Imperial Eastern Region Conferences reconfirmed Japan's commitment to be the dominant power in the Northeast. While the Japanese Army initially justified its presence by stating that it was simply protecting its own economic interests, militarists in the army began pushing for an expansion of influence, leading to the Kwangtung Army assassinating the warlord of Manchuria, Zhang Zuolin, on 4 June 1928. This bombing of Zhang's train was carried out by officers on their own initiative and stood in direct opposition to the Tanaka cabinet's official policy of maintaining good relations with Zhang, illustrating the growing autonomy and civilian-military divide. Following Zhang's death, his son Zhang Xueliang succeeded him, and aligned with Chiang Kai-shek's Nanjing government through the Northeast Flag Replacement in December 1928, symbolically unifying China. In July 1929, Zhang Xueliang moved to assert Chinese sovereignty by ousting Soviet employees from the Chinese Eastern Railway (CER), provoking the five-month-long Sino-Soviet conflict (1929). The Soviet Red Army forces decisively defeated Zhang's Northeastern Army, resulting in the resumption of Soviet control over the railway and the severing of diplomatic relations between Nanjing and Moscow. For Kwantung Army officers, the conflict demonstrated the military vulnerability of the northeastern warlord forces. The conflict shook Japanese policy to the core and reopened the Manchurian problem. By 1930, the Kwantung Army realized they faced a Red Army that was only growing stronger. The time to act was drawing near and Japanese plans to conquer the Northeast were accelerated. The subsequent instability and the erosion of Soviet influence during the Great Depression left a power vacuum in Manchuria that the Kwantung Army sought to exploit. Kwantung Army Colonels Seishirō Itagaki and Kanji Ishiwara independently decided to provoke the invasion of Manchuria with the Mukden incident in September 1931. Kwantung Army soldiers set off a bomb on the South Manchuria Railway in order to provoke an opportunity to act in "self defense". Japan believed its rights in Manchuria, which had been established as a result of its victory in 1905 at the end of the Russo-Japanese War, had been systematically violated and there were "more than 120 cases of infringement of rights and interests, interference with business, boycott of Japanese goods, unreasonable taxation, detention of individuals, confiscation of properties, eviction, demand for cessation of business, assault and battery, and the oppression of Korean residents". After five months of fighting, Japan successfully occupied all of Manchuria, to the surprise of many. Ishiwara himself expected to be arrested for insubordination, but instead was praised for his success. He invented the Concordia Association to establish the puppet state of Manchukuo as an independent country. The last Emperor of China, Puyi, was installed as its puppet ruler. Militarily too weak to challenge Japan directly, China appealed to the League of Nations for help. The League's investigation led to the publication of the Lytton Report, condemning Japan for its incursion into Manchuria, causing Japan to withdraw from the League of Nations. No country took action against Japan beyond tepid censure.
=== Sporadic Japanese encroachment === From 1931 until summer 1937, the Nationalist Army under Chiang Kai-shek did little to oppose Japanese encroachment into China However, Chiang had recognized the incoming threat of a Japanese invasion, and had secretly begun war preparations since 1932, such as creating the National Defense Planning Council, recruiting German military advisors, and purchasing foreign arms.
Incessant fighting followed the Mukden Incident. In 1932, Chinese and Japanese troops clashed in Shanghai during the 28 January battle. This resulted in the demilitarization of Shanghai, which forbade the Chinese to deploy troops in their own city. In Manchukuo, there was an ongoing campaign to pacify the Anti-Japanese Volunteer Armies that arose from widespread outrage over the policy of non-resistance to Japan. On 15 April 1932, the Chinese Soviet Republic led by the Communists declared war on Japan. Under Chi Shi-ying and his protégé Lo Ta-yu's leadership, the Kuomintang also established the Northeast Anti-Manchukuo and Anti-Japanese Association as well as the September 18th Alliance. These organizations developed an extensive underground intelligence network and coordinated anti-Japanese activities in Manchuria. In 1933, the Japanese attacked the Great Wall region. The Tanggu Truce established in its aftermath, gave Japan control of Rehe Province, as well as a demilitarized zone between the Great Wall and Beijing-Tianjin region. Japan aimed to create another buffer zone between Manchukuo and the Chinese Nationalist government in Nanjing. Japan increasingly exploited China's internal conflicts to reduce the strength of its fractious opponents. Even years after the Northern Expedition, the political power of the Nationalist government was limited to just the area of the Yangtze River Delta. Other sections of China were essentially in the hands of local Chinese warlords. Japan sought various Chinese collaborators and helped them establish governments friendly to Japan. This policy was called the Specialization of North China (華北特殊化; huáběitèshūhùa), more commonly known as the North China Autonomous Movement. The northern provinces affected by this policy were Chahar, Suiyuan, Hebei, Shanxi, and Shandong. This Japanese policy was most effective in the area of what is now Inner Mongolia and Hebei. In 1935, under Japanese pressure, China signed the He–Umezu Agreement, which forbade the KMT to conduct party operations in Hebei. In the same year, the Chin–Doihara Agreement was signed expelling the KMT from Chahar. Thus, by the end of 1935 the Chinese government had essentially abandoned northern China. In its place, the Japanese-backed East Hebei Autonomous Council and the Hebei–Chahar Political Council were established. There in the empty space of Chahar the Mongol military government was formed on 12 May 1936. Japan provided all the necessary military and economic aid. Afterwards Chinese volunteer forces continued to resist Japanese aggression in Manchuria, and Chahar and Suiyuan.
=== Continued negotiations === The viability of a Sino-Japanese partnership, initially pursued by Kōki Hirota and Chinese Premier Wang Jingwei, deteriorated rapidly due to domestic political developments in late 1935. In November 1935, the Nationalist government carried out a major currency reform, abandoning the silver standard in favor of the managed Chinese National Currency. Backed by Great Britain and championed by Finance Minister H. H. Kung (a prominent member of China's pro-Western faction), the reform reduced Japanese economic leverage over China's northern provinces. Concurrently, Nanjing's primary advocates for negotiations with Japan were effectively removed from the political landscape: an assassination attempt in November forced Wang Jingwei’s resignation, while key diplomats were lost when Huang Fu retired and Tang Youren was assassinated in December. The establishment of the Japanese-aligned East Hebei Autonomous Government under Yin Ruguang had incited the December 9th Movement, rallying Chinese public opinion against Japan. Despite these setbacks, the pro-appeasement alignment remained influential within the Nationalist government, supported by the official Kuomintang policy of delaying conflict to buy time under what Chiang called, "first internal pacification, then external resistance." General Song Zheyuan's local appeasement strategy in the north led to the establishment of the Hebei–Chahar Political Council. By 1936, the failure of the North China Buffer State Strategy to create Japanese diplomatic leverage and the fallout of the February 26 coup attempt in Tokyo opened the door for more negotiations. The Japanese Army High Command aligned with the civilian government favored direct diplomatic negotiations with Nanjing, moving away from the use of regional proxies. Satō Naotake, the Japanese foreign minister in the Hayashi cabinet, strived to end the buffer state strategy and treat China as an equal to avoid war. Concurrently, the Chinese Communist Party capitalized on anti-Japanese sentiment and Chinese nationalism, advocating for a nationwide ceasefire and resistance. This demand gained significant popular support, as a ceasefire would halt Chiang Kai-shek's anti-communist encirclement campaigns. During the Kawagoe-Chang Chun negotiations in the fall of 1936, Japanese Ambassador Shigeru Kawagoe attempted to secure anti-communist cooperation, but Chinese Foreign Minister Zhang Qun adopted a firmer stance, demanding the dissolution of the East Hebei Autonomous Government and an end to smuggling as preconditions for normalization.
Course of the war
=== 1937: Outbreak of full-scale war === On the night of 7 July 1937, Chinese and Japanese troops exchanged fire in the vicinity of the Marco Polo (or Lugou) Bridge about 16 km from Beijing. The initial confused and sporadic skirmishing was escalated into the first full-scale battle weeks later. However, negotiations continued even past the Battle of Shanghai with the Trautmann mediation and Nine Power Treaty Conference. Total war only commenced after the Battle of Nanking, when Fumimaro Konoe declared that Japan would no longer negotiate with Chiang Kai-Shek. Unlike Japan, China was unprepared for total war and had little military-industrial strength, no mechanized divisions, and few armoured forces. Soon after 1937, local Chinese guerilla forces organized spontaneously. These typically joined either the Communist or Nationalist forces. Within the first year of full-scale war, Japanese forces obtained victories in most major Chinese cities.
Marco Polo Bridge incident
On 7 July, units of the Japanese China Garrison Army crossed the border to conduct military exercises at night, claiming Private Shimura Kikujiro went missing and demanded entry to the walled city of Wanping. The Chinese garrison of the 29th Army refused. Fire was exchanged in the confusion. The question of "who fired first" and provoked the incident is highly contested, and the exact cause of this incident remains unknown. Despite the initial fighting, a ceasefire was negotiated on July 11 in Beijing. The local Japanese military and General Qin Dechun agreed to a settlement: an apology, the withdrawal of Chinese troops from Wanping, and better control of "communists" in the area. However, news of the ceasefire failed to reach the central military command of either China or Japan immediately, and both grew increasingly concerned. Chiang Kai-shek had ordered four Central Army divisions to move into Hebei, even though this violated the He–Umezu Agreement. The following day, the Konoe cabinet held the Five Ministers Conference, where the Imperial Japanese Army General Staff approved a plan that authorized the deployment of three infantry divisions from mainland Japan. Major General Ishiwara tried to oppose the plan as he advocated a policy of non-expansion, but eventually agreed as "to be prepared for any contingency if the situation becomes strained". Although the eventual news of the ceasefire prevented outright war, the arrival of new divisions and the resulting confusion caused tensions to rise. Military cable lines were constantly severed during the tensions. Since October 1936, Moscow had continuously proposed a mutual security pact with China, but the deal was never accepted, even after the December 1936 Xi'an Incident. On 5 June 1937, Soviet leader Joseph Stalin again proposed a mutual security pact to China, but Foreign Minister Wang Chonghui only submitted it to Chiang a day after the Marco Polo Bridge Incident. Chiang immediately tried to accept the mutual security offer, but by then the USSR considered it too late and instead proposed a non-aggression pact. On 16 July, U.S. Secretary of State Cordell Hull issued a public statement of principles advocating for the "sanctity of treaties" and the "abstinence by all nations from use of force." Chiang Kai-shek had been closely monitoring Western reactions, and relied on a long-term strategy of obtaining support from the League of Nations and the world at large to punish Japan. However, as American policy followed what Hull summed up as "keeping this country out of war," the diplomatic signals were intentionally vague to retain impartiality. The CCP's formal declaration for KMT-CCP cooperation was drafted by Zhou Enlai on 4 July 1937 and sent to the Nationalist government on 15 July, though it was not published until 22 September, solidifying the basis for a Second United Front. On 17 July, Chiang Kai-shek delivered the Lushan Statement, framing the incident as a struggle for the nation's survival and declaring that China had reached its "limit of endurance." Chiang outlined his demands for peace to Japan, including that the 29th Army be allowed to move freely in the area. This statement essentially transformed the local incident into a national cause of resistance. Although Chiang was ready to accept the local ceasefire, he slowed the withdrawal from the area to gauge international response. On 25 July, the Langfang Incident occurred when Chinese troops engaged a Japanese communication repair unit. On 26 July, the Guanganmen Incident saw Japanese troops fired upon while attempting to enter Peiping's city gates to protect Japanese nationals. These incidents led the Japanese China Garrison Army to abandon diplomatic efforts and launch a military invasion.
Beiping–Tianjin campaign
On 28 July 1937, the IJA 20th Division and three independent combined brigades launched an offensive against the Chinese 29th Army. The battle involved little combat within Beiping itself, as General Song Zheyuan ordered a general withdrawal of the 29th Army to avoid its total destruction. The Japanese captured the city on July 29 after the Chinese forces withdrew, and majority of intense fighting occurred at Tianjin. The Taku Forts at Tianjin fell on 30 July, concluding the campaign. The Japanese Army had been given orders not to advance further than the Yongding River. The Konoe government's foreign minister opened negotiations with Chiang Kai-shek's government in Nanjing and stated: "Japan wants Chinese cooperation, not Chinese land." After the Tongzhou mutiny on 29 July, Chinese soldiers assigned to a Japanese-backed puppet government mutinied and killed approximately 200 Japanese and Korean civilians. This inflamed anti-Chinese sentiments in Japan, convinced many in the military that escalation in China was necessary.
==== Diplomatic maneuvering ==== On August 6, 1937, Soviet Ambassador Ivan Maisky reportedly assured Chinese officials that if the United States, England, and France offered mediation and Japan rejected it, "the Soviet Union would go to war on the side of China." Chiang Kai-shek, bolstered by these continued Russian promises of armed assistance, "personally wished to fight" rather than accept a diplomatic compromise with Japan. Foreign Minister Kōki Hirota attempted to bring the conflict to a close through the "Funatsu Operation" in early August. Entrusted to Funatsu Tatsuichirō, former consul-general in Shanghai, the plan aimed to negotiate a ceasefire directly with Gao Zongwu, head of the Nationalist foreign ministry's Asian Affairs Bureau, by having Gao submit a Chinese ceasefire proposal to Japanese Ambassador Shigeru Kawagoe. The Japanese terms conveyed by Hirota included establishing a demilitarized zone from Beiping to Tianjin, concluding a Sino-Japanese anti-communist pact, and securing a Chinese promise to not make the existence of Manchukuo an issue in the future. Hirota believed these conditions were highly generous and would be well-received by Nanjing and the international community. However, historians note that the Chinese government viewed these terms as unacceptable because they required severe political concessions. Funatsu contacted Gao on 9 August, but the talks were immediately halted that evening by the Ōyama Incident, when two Japanese naval personnel were killed in Shanghai. Talks officially collapsed on 13 August when the Battle of Shanghai erupted, and the personnel of the Japanese consulate in Nanjing were subsequently withdrawn on 14 August.
Battle of Shanghai
The Imperial General Headquarters (GHQ) in Tokyo was content with the gains acquired in northern China following the Marco Polo Bridge Incident, and initially showed reluctance to escalate the conflict into a full-scale war. However, the situation in Shanghai reached a breaking point on 9 August 1937, when the Ōyama Incident occurred with the shooting of two Japanese officers who were attempting to enter the Hongqiao military airport. The Japanese demanded that all Chinese forces withdraw from Shanghai; the Chinese outright refused to meet this demand. In response, both the Chinese and the Japanese marched reinforcements into the Shanghai area. Chiang concentrated his best troops north of Shanghai in an effort to impress the city's large foreign community and increase China's foreign support. On 13 August 1937, Kuomintang soldiers attacked Japanese Marine positions in Shanghai, with Japanese army troops and marines in turn crossing into the city with naval gunfire support at Zhabei, leading to the Battle of Shanghai. On 14 August, Chinese forces under the command of Zhang Zhizhong were ordered to capture or destroy the Japanese strongholds in Shanghai, leading to bitter street fighting.
Chiang Kai-shek and his generals were influenced by assurances from Soviet Ambassador Dmitry Bogomolov, who had promised that China could expect support from the Soviet Union if it undertook armed resistance. The Sino-Soviet Non-Aggression Pact was signed on August 21 and soon, the USSR delivered military aid through Operation Zet, including aircraft, tanks, equipment, and military advisors. However, the Soviet Union never directly intervened in the war as Chiang had hoped. In late August, the Japanese Army landed reinforcements in northern Shanghai. Chinese commanders quickly rushed forces to counter the landings, resulting in heavy fighting including trench and urban warfare. Both sides suffered high casualty rates in the attrition. As the battle in Shanghai continued, Japan advanced along railway lines in the North, until they reached Jinan and the Yellow River. Alongside Mengjiang forces, Japan invaded Taiyuan and the North China area. By 26 October, the IJA had captured Dachang, a key strong-point within Shanghai, and on 5 November, additional reinforcements from Japan landed in Hangzhou Bay behind Chinese lines. On November 9, the 10th Army reinforced Hangzhou Bay, and the NRA began a general retreat. The Imperial Japanese Army (IJA) ultimately committed over 300,000 troops, along with numerous naval vessels and aircraft, to capture the city. After more than three months of intense fighting, their casualties far exceeded initial expectations. Japan did not immediately occupy the Shanghai International Settlement or the Shanghai French Concession, areas which were outside of China's control due to the treaty port system. Japan moved into these areas after its 1941 declaration of war against the United States and the United Kingdom.
Fall of Nanjing and massacre
Following the Battle of Shanghai, the Army General Staff imposed an "operation restriction line" up to the cities of Suzhou and Jiaxing with the aim of ending the war. Konoe's government presented peace terms to Chiang Kai-shek through the Trautmann Mediation. These term included no demands for territorial annexation, but rather requirements for economic cooperation and an anti-communist pact. Chiang may have been encouraged to hold out in hopes of a Western intervention, after U.S. President Franklin D. Roosevelt delivered his Quarantine Speech in Chicago on October 5, advocating for an international quarantine of aggressor nations. Japan was invited to the Nine Power Treaty Conference in Brussels, but this was denied by Hirota who believed it would 'merely result in bolstering up China and in prolonging rather than shortening the warfare.' While Chiang secretly hoped for FDR to take action to immediately end the war with Japan, the conference ultimately failed to impose sanctions on Japan,. The Japanese military's non-expansion policy was discarded when Japanese generals disobeyed orders and began to pursue retreating Chinese forces past the restriction line on November 19, aiming to encircle Nanjing. The Japanese Army General Staff then authorized the capture of Nanjing on November 28, 1937, to force a conclusion to the conflict.
In November 1937, the Japanese concentrated 220,000 soldiers and began a campaign against Nanjing . Building on the hard-won victory in Shanghai, the IJA advanced on and captured the KMT capital city of Nanjing (December 1937) and Northern Shanxi (September – November 1937). Japanese forces inflicted heavy casualties on the Chinese soldiers defending the city, killing approximately 50,000 of them including 17 Chinese generals. Upon the capture of Nanjing, Japanese committed massive war atrocities including mass murder and rape of Chinese civilians after 13 December 1937, which has been referred to as the Nanjing Massacre. Over the next several weeks, Japanese troops perpetrated numerous mass executions and tens of thousands of rapes. The army looted and burned the surrounding towns and the city, destroying more than a third of the buildings. The number of Chinese killed in the massacre has been subject to much debate, with estimates ranging from 100,000 to more than 300,000. The numbers agreed upon by most scholars are provided by the International Military Tribunal for the Far East, which estimate at least 200,000 murders and 20,000 rapes. The Japanese atrocities in Nanjing, especially following the Chinese defense of Shanghai, increased international goodwill for the Chinese people and the Chinese government. The Nationalist government re-established itself in Chongqing, which became the wartime seat of government until 1945. Following the capture of Nanjing, Chiang Kai-shek was now willing to accept Japan's initial proposal. However, the Japanese government hardened its terms drastically with the inclusion of the recognition of Manchukuo. Peace negotiations broke down and Chiang Kai-shek failed to respond by the January 12, 1938 deadline. Prime Minister Konoe issued the First Konoe Statement on January 16, 1938, declaring: "We will no longer deal with the government of Chiang Kai-shek." This effectively severed relations and committed Japan to a total war of regime change.
Xinjiang rebellion
In 1937, then pro-Soviet General Sheng Shicai invaded Dunganistan accompanied by Soviet troops to defeat General Ma Hushan of the KMT 36th Division. General Ma expected help from Nanjing, but did not receive it. The Nationalist government was forced to deny these maneuvers as "Japanese propaganda", as it needed continued military supplies from the Soviets.
=== 1938: Strategic retreat === By January 1938, most conventional Kuomintang forces had either been defeated or no longer offered major resistance to Japanese advances. KMT forces won a few victories in 1938 (the Battle of Taierzhuang and the Battle of Wanjialing) but were generally ineffective that year. By March 1938, the Japanese controlled almost all of North China. Communist-led rural resistance to the Japanese remained active, however. Following the fall of Shanghai and Nanjing in late 1937, the Nationalist military command began a war of attrition known as "trading space for time" (以空間換時間). By gradually withdrawing into China's vast interior and establishing the rugged southwestern province of Sichuan as a final defensive base, the Kuomintang intended to over-extend Japanese supply lines while reconstituting its depleted central armies.
Xuzhou and Wuhan
With many victories achieved, Japanese field generals escalated the war in Jiangsu in an attempt to wipe out the Chinese forces in the area. The Japanese managed to overcome Chinese resistance around Bengbu and the Teng xian, but were fought to a halt at Linyi. The Japanese were then decisively defeated at the Battle of Taierzhuang (March–April 1938), where the Chinese used night attacks and close-quarters combat to overcome Japanese advantages in firepower. The Chinese also severed Japanese supply lines from the rear, forcing the Japanese to retreat in the first Chinese victory of the war. The Japanese then attempted to surround and destroy the Chinese armies in the Xuzhou region with an enormous pincer movement. However the majority of the Chinese forces, some 200,000–300,000 troops in 40 divisions, managed to break out of the encirclement and retreat to defend Wuhan, the Japanese's next target.
Following Xuzhou, the IJA changed its strategy and deployed almost all of its existing armies in China to attack the city of Wuhan, which had become the political, economic and military center of China, in hopes of destroying the fighting strength of the NRA and forcing the KMT government to negotiate for peace. On 6 June, they captured Kaifeng, the capital of Henan, and threatened to take Zhengzhou, the junction of the Pinghan and Longhai railways. The Japanese forces, numbering some 400,000 men, were faced by over 1 million NRA troops in the Central Yangtze region. Having learned from their defeats at Shanghai and Nanjing, the Chinese had adapted themselves to fight the Japanese and managed to check their forces on many fronts, slowing and sometimes reversing the Japanese advances, as in the case of Wanjialing. To overcome Chinese resistance, Japanese forces frequently deployed poison gas and committed atrocities against civilians, such as a "mini-Nanjing Massacre" in the city of Jiujiang upon its capture. After four months of intense combat, the Nationalists were forced to abandon Wuhan by October, and its government and armies retreated to Chongqing. Both sides had suffered tremendous casualties in the battle, with the Chinese losing up to 500,000 soldiers killed or wounded, and the Japanese up to 200,000.
