Although the two countries had fought intermittently since 1931, full-scale war started in earnest in 1937 and ended only with the surrender of Japan in 1945. The war was the result of a decades-long Japanese imperialist policy aiming to dominate China politically and militarily to secure its vast raw material reserves and other resources. At the same time, the rising tide of Chinese nationalism and notions of self determination stoked the coals of war. Before 1937, China and Japan fought in small, localized engagements in so-called "incidents". Yet the two sides, for a variety of reasons, refrained from fighting a total war. The 1931 invasion of Manchuria by Japan is known as the "Mukden Incident". The last of these incidents was the Marco Polo Bridge Incident of 1937, marking the official beginning of full scale war between the two countries.
In Japan, the name is most commonly used because of its neutrality. When the war began in July 1937 near Beijing, the government of Japan used North China Incident (北支事変, Hokushi Jihen), and with the outbreak of war in Central China next month, it was changed to China Incident (支那事変, Shina Jihen).
The word incident (事変, jihen) was used by Japan as neither country had declared war on each other. Japan wanted to avoid intervention by other countries such as the United Kingdom and particularly the United States, which had been the biggest steel exporter to Japan. American President Franklin D. Roosevelt would have had to impose an embargo due to the Neutrality Acts had the fighting been named a war.
In Japanese propaganda however, the invasion of China became a "holy war" (seisen), the first step of the Hakko ichiu (eight corners of the world under one roof). In 1940, prime minister Konoe thus launched the League of Diet Members Believing the Objectives of the Holy War. When both sides formally declared war in December 1941, the name was replaced by Greater East Asia War (大東亜戦争, Daitōa Sensō).
Although the Japanese government still uses "China Incident" in formal documents, because the word Shina is considered a derogatory word by China, media in Japan often paraphrase with other expressions like The Japan-China Incident (日華事変 [Nikka Jihen], 日支事変 [Nisshi Jihen], which were used by media even in the 1930s.
Also, the name Second Sino-Japanese War is not usually used in Japan, as the First Sino-Japanese War (日清戦争, Nisshin-Sensō), between Japan and the Qing Dynasty in 1894 is not regarded to have obvious direct linkage with the second, between Japan and the Republic of China.
The origin of the Second Sino-Japanese War can be traced to the First Sino-Japanese War of 1894-95, in which China, then under the Qing Dynasty, was defeated by Japan and was forced to cede Taiwan and recognize the independence of Korea in the Treaty of Shimonoseki. The Qing Dynasty was on the brink of collapse from internal revolts and foreign imperialism, while Japan had emerged as a great power through its effective measures of modernization. The Republic of China was founded in 1912, following the Xinhai Revolution which overthrew the Qing Dynasty. However, the nascent Republic was even weaker than its predecessor because of the dominance of warlords. Unifying the nation and repelling imperialism seemed a very remote possibility. Some warlords even aligned themselves with various foreign powers in an effort to wipe each other out. For example, warlord Zhang Zuolin of Manchuria openly cooperated with the Japanese for military and economic assistance. It was during the early period of the Republic that Japan became the greatest foreign threat to China.
In 1915, Japan issued the Twenty-One Demands to further its political and commercial interests in China. Following World War I, Japan acquired the German sphere of influence in Shandong. China under the Beiyang government remained fragmented and unable to resist foreign incursions until the Northern Expedition of 1926-28, launched by the Kuomintang (KMT, or Chinese Nationalist Party) in Guangzhou against various warlords. The Northern Expedition swept through China until it was checked in Shandong, where Beiyang warlord Zhang Zongchang, backed by the Japanese, attempted to stop the Kuomintang Army from unifying China. This situation culminated in the Jinan Incident of 1928 in which the Kuomintang army and the Japanese were engaged in a short conflict. In the same year, Manchurian warlord Zhang Zuolin was also assassinated when he became less willing to cooperate with Japan. Following these incidents, the Kuomintang government under Chiang Kai-shek finally succeeded in unifying China in 1928.
Still, numerous conflicts between China and Japan persisted as Chinese nationalism had been on the rise and one of the ultimate goals of the Three Principles of the People was to rid China of foreign imperialism. However, the Northern Expedition had only nominally unified China, and civil wars broke out between former warlords and rival Kuomintang factions. In addition, the Chinese Communists revolted against the central government following a purge of its members from the KMT. Because of these situations, the Chinese central government diverted much attention into fighting these civil wars and followed a policy of "first internal pacification before external resistance". This situation provided an easy opportunity for Japan to further its goals. In 1931, the Japanese invaded Manchuria right after the Mukden Incident. After five months of fighting, in 1932, the puppet state Manchukuo was established with the last emperor of China, Puyi, installed as its head of state. Unable to challenge Japan directly, China appealed to the League of Nations for help. The League's investigation was published as the Lytton Report, which condemned Japan for its incursion of Manchuria, and led Japan to withdraw from the League of Nations. From the late 1920s and throughout the 1930s, appeasement was the policy of the international community and no country was willing to take an active stance other than a weak censure. Japan saw Manchuria as a limitless supply of raw materials and as a buffer state against the Soviet Union.
Incessant conflicts followed the Mukden Incident. In 1932, Chinese and Japanese soldiers fought a short war in the January 28 Incident. The war resulted in the demilitarization of Shanghai, which forbade the Chinese from deploying troops in their own city. In Manchukuo there was an ongoing campaign to defeat the volunteer armies that arose from the popular frustration at the policy of nonresistance to the Japanese. In 1933, the Japanese attacked the Great Wall region, and in its wake the Tanggu Truce was signed, which gave Japan the control of Rehe province and a demilitarized zone between the Great Wall and Beiping-Tianjin region. The Japanese aim was to create another buffer region, this time between Manchukuo and the Chinese Nationalist government whose capital was Nanjing.
In addition, Japan increasingly utilized the internal conflicts among the Chinese factions to reduce their strength one by one. This was precipitated by the fact that even some years after the Northern Expedition, the political power of the Nationalist government only extended around the Yangtze River Delta region, and other regions of China were essentially held in the hands of regional powers. Japan sought various Chinese collaborators and helped these men lead governments that were friendly to Japan. This policy was called the Specialization of North China or 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 from conducting party operations in Hebei. In the same year, the Ching-Doihara Agreement was signed and vacated the KMT from Chahar. Thus, by the end of 1935, the Chinese central government had virtually vacated North China. In its place, the Japanese-backed East Hebei Autonomous Council and the Hebei-Chahar Political Council were established. There in the vacated area of Chahar the Mongol Military Government (蒙古軍政府) was formed on May 12 1936 with Japan providing military and economic aid.
Most historians place the beginning of the Second Sino-Japanese War on July 7, 1937 at the Marco Polo Bridge Incident, when a crucial access point to Beijing was assaulted by the Imperial Japanese Army (IJA). Because the Chinese defenders were the poorly equipped infantry divisions of the former Northwest Army, the Japanese easily captured Beiping and Tianjin.
The Imperial General Headquarters in Tokyo were initially reluctant to escalate the conflict into full scale war, being content with the victories achieved in northern China following the Marco Polo Bridge Incident. However, the KMT central government determined that the "breaking point" of Japanese aggression had been breached and Chiang Kai-shek quickly mobilized the central government army and airforce under his direct command to attack the Japanese Marines in Shanghai, which led to the Battle of Shanghai. The IJA had to mobilize over 200,000 troops, coupled with numerous naval vessels and aircraft to capture Shanghai after more than three months of intense fighting, with casualties far exceeding initial expectations.
Building on the hard won victory in Shanghai, the IJA captured the KMT capital city of Nanjing and Southern Shanxi in campaigns involving approximately 350,000 Japanese soldiers, and considerably more Chinese soldiers. Historians estimate up to 300,000 people perished in the Nanking Massacre, after the fall of Nanjing on December 13, 1937, while some Japanese historians wrongly deny the existence of a massacre.
At this point the Headquarters in Tokyo still hoped to limit the scope of the conflict at occupying areas around Shanghai, Nanjing and most of northern China, in order to preserve strength for an anticipated showdown with the Soviet Union. But by now the Headquarters had effectively lost command over Japanese generals fighting in China. With many victories achieved, these generals escalated the war and finally met with defeat in Taierzhuang. Afterwards the IJA had no choice but to fight on, hoping to destroy the fighting strength of the National Revolutionary Army (NRA) and force the KMT government to negotiate the terms for surrender. The height of Japanese army full-scale attacks cumulated in capturing the city of Wuhan in October, 1938, but it failed to destroy the NRA as the KMT retreated to Chongqing to set up a provisional capital and Chiang refused to negotiate unless the Japanese agree to a complete withdrawal to 1937 levels.
While the KMT central government struggled on from the provisional capital of Chongqing, Chiang Kai-shek's stern refusal to surrender after suffering tremendous losses deeply fustrated the IJA, therefore in retaliation throughout the next few years the Imperial air force of the Navy and the Army began launching the world's first massive air bombing raids of civilian targets on nearly every major city in unoccupied China, leaving millions dead, injured and homeless.
The Japanese tried to solve its occupation problems by implementing a strategy of creating friendly puppet governments favorable to Japanese interests in the territories conquered, the most prominent being the Nanjing Nationalist Government headed by former KMT premier Wang Jingwei. However, the atrocities committed by the Japanese army, as well as Japanese refusal to yield any real power made them very unpopular and ineffective. The only success the Japanese had was the ability to recruit a large Collaborationist Chinese Army to maintain public security in the occupied areas.
With very low military-industrial capacities and limited experience in modern warfare, the NRA was defeated in a large-scale counter-offensive against IJA in early 1940. Afterwards Chiang could not risk any more all-out offensive campaigns given the poorly-trained, under-equipped, and disorganized state of his armies and opposition to his leadership both within Kuomintang and in China at large. He had lost a substantial portion of his best trained and equipped army defending Shanghai and was at times at the mercy of his generals, who maintained a high degree of independence from the central KMT government.
On the other hand, while Japan held most of the eastern coastal areas of China and Vietnam, guerrilla fighting continued in the conquered areas. Japan had suffered tremendous casualties from unexpectedly stubborn resistance in China and already developed problems in administering and garrisoning the seized territories. Neither side could make any swift progress in a manner resembling the fall of France and Western Europe to Nazi Germany.
The basis of Chinese strategy before the entrance of Western Allies can be divided into two periods:
Unlike Japan, China was unprepared for total war and had little military-industrial strength, no mechanized divisions, and few armored forces. Up until the mid-1930s China had hoped that the League of Nations would provide countermeasures to Japan's aggression. In addition, the Kuomintang government was mired in a civil war against the Communists, as Chiang Kai-shek was famously quoted: "the Japanese are a disease of the skin, the Communists are a disease of the heart". The United Front between KMT and CCP was never truly unified, as each side was preparing for a showdown with the other once the Japanese were driven out.
Even under these extremely unfavorable circumstances, Chiang realized that in order to win the support from the United States and other foreign nations, China must prove that it was indeed capable of fighting. A fast retreat would discourage foreign aid so Chiang decided to make a stand in the Battle of Shanghai. Chiang sent the best of his German-trained divisions to defend China's largest and most industrialized city from the Japanese. The battle lasted over three months, saw heavy casualties on both sides and ended with a Chinese retreat towards Nanjing. While this was a military defeat for the Chinese, it proved that China would not be defeated easily and showed China's determination to the world, which became an enormous morale booster for the Chinese people as it ended the Japanese taunt that Japan could conquer Shanghai in three days and China in three months.
Afterwards the Chinese began to adopt the strategy of "trading space for time" (Chinese: 以空間換取時間). The Chinese army would put up fights to delay Japanese advance to northern and eastern cities, to allow the home front, along with its professionals and key industries, to retreat west into Chongqing. As a result of Chinese troops' scorched earth strategies, where dams and levees were intentionally sabotaged to create massive flooding, the consecutive Japanese advancements and conquests began to stall in late-1938.
Second Period: 25 October 1938 (Fall of Wuhan) - December 1941 (before the Allie's declaration of war on Japan).
During this period, the Chinese main objective was to prolong the war and waited for the Japanese to make the mistake of attacking the United States. American general Joseph Stilwell called this strategy "winning by outlasting". Therefore the Chinese army adopted the concept of "magnetic warfare" to attract advancing Japanese troops to definite points where they were subjected to ambush, flanking attacks, and encirclements in major engagements. The most prominent example of this tactic is the successful defense of Changsha numerous times.
Also, CCP and other local guerrillas forces continued their resistance in occupied areas to pester the enemy and make their administration over the vast lands of China difficult. As a result the Japanese really only controlled the cities and railroads, while the countrysides were almost always hotbeds of partisan activity.
By 1940, the war had reached a stalemate with both sides making minimal gains. The Chinese had successfully defended their land from oncoming Japanese on several occasions, while strong resistance in areas occupied by the Japanese made a victory seem impossible to the Japanese. This frustrated the Japanese and led them to employ the "Three Alls Policy" (kill all, loot all, burn all) (三光政策, Hanyu Pinyin: Sānguāng Zhèngcè, Japanese On: Sankō Seisaku). It was during this time period that the bulk of Japanese atrocities were committed.
After the Mukden Incident, Chinese public opinion strongly criticized the leader of Manchuria, the "young marshal" Zhang Xueliang, for his nonresistance to the Japanese invasion, even though the Kuomintang central government was indirectly responsible for this policy. Afterwards Chiang Kai-shek assigned Zhang and his Northeast Army the duty of suppressing the Red Army of the Chinese Communist Party(CCP) in Shaanxi after their Long March. This resulted in great casualties for his Northeast Army, and Chiang Kai-shek did not give him any support in manpower and weaponry.
On 12 December, 1936 a deeply disgruntled Zhang decided to conspire with the CCP and kidnapped Chiang Kai-shek in Xi'an. In order to secure the release of Chiang, the KMT was forced to agree to a temporary end to the Chinese Civil War and the forming of a United Front between the CCP and KMT against Japan on 24 December 1936. The cooperation took place with salutary effects for the beleaguered CCP, and they agreed to form the New Fourth Army and the 8th Route Army which were nominally under the command of the National Revolutionary Army. The Red Army of CCP fought in alliance with the KMT forces during the battle of Taiyuan, and the high point of their cooperation came in 1938 during the Battle of Wuhan.
However, despite Japan's steady territorial gains in northern China, the coastal regions, and the rich Yangtze River Valley in central China, the distrust between the two antagonists was scarcely veiled. As a result of the Communists efforts to aggressively expand their military strength through absorbing Chinese guerrilla forces behind enemy lines (frequently by the use of force), the uneasy alliance began to break down by late 1938. Starting in 1940, open conflicts between the Nationalists and Communists became more frequent in the occupied areas outside of Japanese control, culminating in the New Fourth Army Incident.
Afterwards, the Second United Front completely broke down and the CCP begin to build up their sphere of influence wherever opportunities were presented, mainly through rural mass organizations, administrative, land and tax reform measures favoring poor peasants; while the Nationalists attempted to neutralize the spread of Communist influence by military blockade of areas controlled by CCP and fighting the Japanese at the same time
See also: Motives of the Second Sino-Japanese War
At the outbreak of full scale war, many global powers were reluctant to provide support to China; because in their opinion the Chinese would eventually lose the war, and they did not wish to antagonize the Japanese who might, in turn, eye their colonial possessions in the region. They expected any support given to Kuomintang might worsen their own relationship with the Japanese, who taunted the Kuomintang with the prospect of conquest within three months.
However, Germany and the Soviet Union did provide support to the Chinese before the war escalated to the Asian theatre of World War II. Prior to the outbreak of the war, Germany and China had close economic and military cooperation, with Germany helping China modernize its industry and military in exchange for raw materials. More than half of the German arms exports during its rearmament period were to China. Nevertheless the proposed 30 new divisions equipped and trained with German assistance did not materialize when Germany withdrew its support in 1938. The Soviet Union wished to keep China in the war to hinder the Japanese from invading Siberia, thus saving itself from a two front war. In September 1937 the Soviet leadership signed Sino-Soviet Non-Aggression Pact, began aiding China and approved Operation Zet, a Soviet volunteer air force. As part of the secret operation Soviet technicians upgraded and handled some of the Chinese war-supply transport. Bombers, fighters, military supplies and advisors arrived, including future Soviet war hero Georgy Zhukov, who won the Battle of Halhin Gol. Prior to the entrance of Western allies, the Soviet Union provided the largest amount of foreign aid to China, totalling some $250 million of credits in munitions and supplies. In 1941 Soviet aid ended as a result of the Soviet-Japanese Neutrality Pact and the beginning of Great Patriotic War. This pact enabled the Soviet Union to avoid fighting against Germany and Japan at the same time.
From December 1937 events such as the Japanese attack on the USS Panay and the Nanking Massacre swung public opinion in the West sharply against Japan and increased their fear of Japanese expansion, which prompted the United States, the United Kingdom, and France to provide loan assistance for war supply contracts to Kuomintang. Furthermore, Australia prevented a Japanese Government-owned company from taking over an iron mine in Australia, and banned iron ore exports in 1938. Japan retaliated by invading Vietnam in 1940, and successfully blockaded China and prevented the import of arms, fuel and 10,000 tons/month of materials supplied by the Western Powers through the Haiphong-Yunnan Fou railway line.
By mid-1941, the United States organized the American Volunteer Group, or Flying Tigers. Led by Claire Chennault, their early combat success of 300 kills against a loss of 12 of their shark painted P-40 fighters earned them wide recognition at the time when Allies were suffering heavy losses. Entering soon after the U.S. and Japan were at war, their dogfighting tactics would be adopted by US forces. They would also transmit the appreciative Chinese thumbs-up gesture for number one into military culture. In addition, the United States, Britain and the Netherlands East Indies began oil and/or steel embargos. The loss of oil imports made it impossible for Japan to continue operations in China. This set the stage for Japan to launch a series of military attacks against the western Allies when the Imperial Navy raided Pearl Harbor on December 8 1941 (December 7 in U.S. time zones).
Within a few days of the attack on Pearl Harbor, both the United States and China officially declared war against Japan. Chiang Kai-shek continued to receive supplies from the United States, as the Chinese conflict was merged into the Asian theatre of World War II. However, in contrast to the Arctic supply route to the Soviet Union that stayed open most of the war, sea routes to China had long been closed, so between the closing of the Burma Road in 1942 and its re-opening as the Ledo Road in 1945, foreign aid was largely limited to what could be flown in over The Hump. Most of China's own industry had already been captured or destroyed by Japan, and the Soviet Union could spare little from the Eastern Front. Because of these reasons, the Chinese government never had the supplies and equipment needed to mount a major offensive.
Chiang was appointed Allied Commander-in-Chief in the China theater in 1942. General Joseph Stilwell served for a time as Chiang's Chief of Staff, while commanding US forces in the China Burma India Theater. However, relations between Stilwell and Chiang soon broke down for many reasons. Many historians (such as Barbara Tuchman) suggested it was largely due to the corruption and inefficiency of the Chinese government. However, other historians (such as Ray Huang) found that it was a more complicated situation. Stilwell had a strong desire to assume total control of Chinese troops, which Chiang vehemently opposed. Stilwell also did not appreciate the complexity of the situation, including the buildup of the Chinese Communists during the war (essentially Chiang had to fight a multi-front war - the Japanese on one side, the Communists on the other). Stilwell openly criticized the Chinese government's conduct of the war in the American media, and to President Franklin D. Roosevelt. Chiang was hesitant to deploy more Chinese troops away from the main front because China already suffered tens of millions of war casualties, and believed that Japan would eventually capitulate to America's overwhelming industrial output and manpower. Therefore the Allies began to lose confidence in the Chinese ability to conduct offensive operations from the Asian mainland, and instead concentrated their efforts against the Japanese in the Pacific Ocean Areas and South West Pacific Area, employing an island hopping strategy.
Conflicts among China, the United States, and the United Kingdom also emerged in the Pacific war. Winston Churchill was reluctant to devote British troops, the majority of whom were defeated by the Japanese in earlier campaigns, to reopen the Burma Road. On the other hand, Stilwell believed that the reopening of the Burma Road was vital to China as all the ports on mainland China were under Japanese control. Churchill's "Europe First" policy obviously did not sit well with Chiang. Furthermore, the later British insistence that China send in more and more troops into Indochina in the Burma Campaign was regarded as an attempt by Great Britain to use Chinese manpower to secure Britain's colonial holdings in Southeast Asia and prevent the gate to India from falling to Japan. Chiang also believed that China should divert its troops to eastern China to defend the airbases of the American bombers, a strategy that U.S. General Claire Chennault supported. In addition, Chiang voiced his support of Indian independence in a meeting with Mahatma Gandhi in 1942, which further soured the relationship between China and the United Kingdom.
The United States saw the Chinese theater as a means to tie up a large number of Japanese troops, as well as being a location for American airbases from which to strike the Japanese home islands. In 1944, as the Japanese position in the Pacific was deteriorating fast, the Imperial Japanese Army launched Operation Ichigo to attack the airbases which had begun to operate. This brought the Hunan, Henan, and Guangxi provinces under Japanese administration. The failure of the Chinese forces to defend these areas led to the replacement of Stilwell by Major General Albert Wedemeyer. However, Chinese troops under the command of Sun Li-jen drove out the Japanese in North Burma to secure the Ledo Road, a supply route to China. In Spring 1945 the Chinese launched offensives and retook Hunan and Guangxi. With the Chinese army well in the progress training and equipping, Albert Wedemeyer planned to launch Operation Carbonado in summer 1945 to retake Guangdong, obtaining a coastal port, and from there drive northwards toward Shanghai. However, the dropping of the atomic bombs hastened Japanese surrender and these plans were not put into action.
As of mid 1945, all sides expected the war to continue for at least another year. On August 6, an American B-29 bomber dropped the first atomic bomb used in combat on Hiroshima. On August 9, the Soviet Union renounced its non-aggression pact with Japan and attacked the Japanese in Manchuria, fulfilling its Yalta Conference pledge to attack the Japanese within three months after the end of the war in Europe. The attack was made by three Soviet army groups. In less than two weeks the Kwantung Army in Manchuria, consisting of over a million men but lacking in adequate armor, artillery, or air support, and depleted of many of its best soldiers by the demands of the Allies' Pacific drive, had been destroyed by the Soviets. Later in the day on August 9, a second atomic bomb was dropped by the United States on Nagasaki. Emperor Hirohito officially capitulated to the Allies on August 15, 1945, and the official surrender was signed aboard the battleship USS Missouri on September 2. The Japanese troops in China formally surrendered on September 9, 1945 and by the provisions of the Cairo Conference of 1943, Manchuria, Taiwan and Pescadores Islands were reverted to China.
In 1945 China emerged from the war nominally a great military power but was actually a nation economically prostrated and on the verge of all-out civil war. The economy deteriorated, sapped by the military demands of a long, costly war and internal strife, by spiraling inflation, and by Nationalist profiteering, speculation, and hoarding. Starvation came in the wake of the war, as large swathes of the prime farming areas had been ravaged by the fighting. Millions were rendered homeless by floods and the destruction of towns and cities in many parts of the country. The problems of rehabilitating the formerly Japanese-occupied areas and of reconstructing the nation from the ravages of a protracted war were staggering.
The situation was further complicated by an Allied agreement at the Yalta Conference in February 1945 that brought Soviet troops into Manchuria to hasten the termination of war against Japan. Although the Chinese had not been present at Yalta, they had been consulted; they had agreed to have the Soviets enter the war in the belief that the Soviet Union would deal only with the Nationalist government. After the war, the Soviet Union, as part of the Yalta agreement's allowing a Soviet sphere of influence in Manchuria, dismantled and removed more than half the industrial equipment left there by the Japanese. The Soviet presence in northeast China enabled the Communists to move in long enough to arm themselves with the equipment surrendered by the withdrawing Japanese army.
The war left the Nationalists severely weakened and their policies left them unpopular. Meanwhile the war strengthened the Communists, both in popularity and as a viable fighting force. At Yan'an and elsewhere in the liberated areas, Mao Zedong was able to adapt Marxism-Leninism to Chinese conditions. He taught party cadres to lead the masses by living and working with them, eating their food, and thinking their thoughts. When this failed, however, more repressive forms of coercion, indoctrination and ostracization were also employed. The Red Army fostered an image of conducting guerrilla warfare in defense of the people. In addition, the Chinese Communist Party (CCP) was effectively split into "Red" (cadres working in the liberated areas) and "White" (cadres working underground in enemy-occupied territory) spheres, a split that would later sow future factionalism within the CCP. Communist troops adapted to changing wartime conditions and became a seasoned fighting force. Mao also began preparing for the establishment of a new China, well away from the front at his base in Yan'an. In 1940 he outlined the program of the Chinese Communists for an eventual seizure of power and began his final push for consolidation of CCP power under his authority. His teachings became the central tenets of the CCP doctrine that came to be formalized as "Mao Zedong Thought". With skillful organizational and propaganda work, the Communists increased party membership from 100,000 in 1937 to 1.2 million by 1945. Soon, all out war broke out between the KMT and CCP, a war that would leave the Nationalists banished to Taiwan and the Communists victorious on the mainland.
The question as to which political group directed the Chinese war effort and exerted most of the effort to resist the Japanese remains a controversial issue.
In the Chinese People's War of Resistance Against Japan Memorial near the Marco Polo Bridge and in mainland Chinese textbooks, the People's Republic of China (PRC) claims that the Nationalists mostly avoided fighting the Japanese in order to preserve its strength for a final showdown with the Communists, while the CCP directed Chinese resistance efforts against the Japanese invasion. Recently, however, with a change in the political climate, the CCP has admitted that certain Nationalist generals made important contributions in resisting the Japanese. The official history in mainland China now states that the KMT fought a bloody, yet indecisive, frontal war against Japan, while the CCP engaged the Japanese forces in far greater numbers behind enemy lines. For the sake of Chinese reunification and appeasing the ROC on Taiwan, the PRC has begun to "acknowledge" the Nationalists and the Communists as "equal" contributors, because the victory over Japan belonged to the Chinese people, rather than to any political party.
Leaving aside Nationalists sources, scholars researching third party Japanese and Soviet sources have documented quite a different view. Such studies claim that the Communists actually played a minuscule involvement in the war against the Japanese compared to the Nationalists and used guerrilla warfare as well as opium sales to preserve its strength for a final showdown with the Kuomintang. This is congruent with the Nationalist viewpoint, as demonstrated by history textbooks published in Taiwan, which gives the KMT credit for the brunt of the fighting. According to these third-party scholars, the Communists were not the main participants in any of the 22 major battles, most involving more than 100,000 troops on both sides, between China and Japan. Soviet liaison to the Chinese Communists Peter Vladimirov documented that he never once found the Chinese Communists and Japanese engaged in battle during the period from 1942 to 1945. He also expressed frustration at not being allowed by the Chinese Communists to visit the frontline, although as a foreign diplomat Vladimirov may have been overly optimistic to expect to be allowed to join Chinese guerrilla sorties. The Communists usually avoided open warfare (the Hundred Regiments Campaign and the Battle of Pingxingguan are notable exceptions), preferring to fight in small squads to harass the Japanese supply lines. In comparison, right from the beginning of the war the Nationalists committed their best troops (including the 36th, 87th, 88th divisions, the crack divisions of Chiang's Central Army) to defend Shanghai from the Japanese. The Japanese considered the Kuomintang rather than the Communists as their main enemy and bombed the Nationalist wartime capital of Chongqing to the point that it was the most heavily bombed city in the world to date. The KMT army suffered some 3.2 million casualties while the CCP increased its military strength from minimally significant numbers to 1.7 million men. This change in strength was a direct result of Japanese forces fighting mainly in Central and Southern China, away from major Communist strongholds such as those in Shaanxi.
While the PRC government has been accused of greatly exaggerating the CCP's role in fighting the Japanese, the legacy of the war is more complicated in the Republic of China on Taiwan. Traditionally, the government has held celebrations marking the Victory Day on September 9 (now known as Armed Forces Day), and Taiwan's Retrocession Day on October 25. However, with the power transfer from KMT to the pro-Taiwan independence Democratic Progressive Party in 2000 and the rise of desinicization, events commemorating the war have become less commonplace. Many supporters of Taiwan independence see no relevance in preserving the memory of the war of resistance that happened primarily on mainland China (some native Taiwanese were even drafted into the IJA and fought for Japan). Still, many KMT supporters, particularly veterans who retreated with the government in 1949, still have an emotional interest in the war. For example, in celebrating the sixtieth anniversary of the end of war in 2005, the cultural bureau of KMT stronghold Taipei held a series of talks in the Sun Yat-sen Memorial Hall regarding the war and post-war developments, while the KMT held its own exhibit in the KMT headquarters. In 2008 KMT won the presidential election, which will impact the government position once more.
To this day the war is a major point of contention between China and Japan. The war remains a major roadblock for Sino-Japanese relations, and many people, particularly in China, harbour grudges over the war and related issues. A small but vocal group of Japanese nationalists and/or right-wingers deny a variety of crimes attributed to Japan. The Japanese invasion of its neighbours is often glorified or whitewashed, and wartime atrocities, most notably the Nanjing Massacre, comfort women, and Unit 731, are frequently denied by such individuals. The Japanese government has also been accused of historical revisionism by allowing the approval of school textbooks omitting or glossing over Japan's militant past. In response to criticism of Japanese textbook revisionism, the PRC government has been accused of using the war to stir up already growing anti-Japanese feelings in order to whip up nationalistic sentiments and divert its citizens' minds from internal matters.
The conflict lasted for 8 years, 1 month, and 3 days (measured from 1937 to 1945).
Chinese sources list the total number of military and non-military casualties, both dead and wounded, at 35 million. Most Western historians believed that the total number of casualties was at least 20 million. The property loss suffered by the Chinese was valued at 383 billion US dollars according to the currency exchange rate in July 1937, roughly 50 times the GDP of Japan at that time (US$7.7 billion).
The National Revolutionary Army (NRA) throughout its lifespan employed approximately 4,300,000 regulars, in 370 Standard Divisions (正式師), 46 New Divisions (新編師), 12 Cavalry Divisions (騎兵師), 8 New Cavalry Divisions (新編騎兵師), 66 Temporary Divisions (暫編師), and 13 Reserve Divisions (預備師), for a grand total of 515 divisions. However, many divisions were formed from two or more other divisions, and many were not active at the same time. The number of active divisions, at the start of the war in 1937, was about 170 NRA divisions. The average NRA division had 4,000–5,000 troops. A Chinese army was roughly the equivalent to a Japanese division in terms of manpower but the Chinese forces largely lacked artillery, heavy weapons, and motorized transport. The shortage of military hardware meant that three to four Chinese armies had the firepower of only one Japanese division. Because of these material constraints, available artillery and heavy weapons were usually assigned to specialist brigades rather than to the general division, which caused more problems as the Chinese command structure lacked precise coordination. The relative fighting strength of a Chinese division was even weaker when relative capacity in aspects of warfare, such as intelligence, logistics, communications, and medical services, are taken into account.
The National Revolutionary Army can be divided roughly into two groups. The first one is the so-called dixi (嫡系, "direct descent") group, which comprised divisions trained by the Whampoa Military Academy and loyal to Chiang Kai-shek, and can be considered the Central Army (中央軍) of the NRA. The second group is known as the zapai (雜牌, "miscellaneous units"), and comprised all divisions led by non-Whampoa commanders, and is more often known as the Regional Army or the Provincial Army (省軍). Even though both military groups were part of the National Revolutionary Army, their distinction lies much in their allegiance to the central government of Chiang Kai-shek. Many former warlords and regional militarists were incorporated into the NRA under the flag of the Kuomintang, but in reality they retained much independence from the central government. They also controlled much of the military strength of China, the most notable of them being the Guangxi, Shanxi, Yunnan and Ma Cliques.
Although during the war the Chinese Communist forces fought as a nominal part of the NRA, the number of those on the CCP side, due to their guerrilla status, is difficult to determine, though estimates place the total number of the Eighth Route Army, New Fourth Army, and irregulars in the Communist armies at 1,300,000.
For more information of combat effectiveness of communist armies and other units of Chinese forces see Chinese armies in the Second Sino-Japanese War.
The Central Army possessed 80 Army infantry divisions with approximately 8,000 men each, nine independent brigades, nine cavalry divisions, two artillery brigades, 16 artillery regiments and three armored battalions. The Chinese Navy displaced only 59,000 tonnes and the Chinese Air Force comprised only about 700 obsolete aircraft.
Chinese weapons were mainly produced in the Hanyang and Guangdong arsenals. However, for most of the German-trained divisions, the standard firearms were German-made 7.92 mm Gewehr 98 and Karabiner 98k. A local variant of the 98k style rifles were often called the "Chiang Kai-shek rifle" a Chinese copy from the Mauser Standard Modell. Another rifle they used was Hanyang 88. The standard light machine gun was a local copy of the Czech 7.92 mm Brno ZB26. There were also Belgian and French LMGs. Surprisingly, the NRA did not purchase any of the famous Maschinengewehr 34s from Germany, but did produce their own copies of them. On average in these divisions, there was one machine gun set for each platoon. Heavy machine guns were mainly locally-made 1924 water-cooled Maxim guns, from German blueprints. On average every battalion would get one HMG. The standard sidearm was the 7.63 mm Mauser M1932 semi-automatic pistol.
Some divisions were equipped with 37 mm PaK 35/36 anti-tank guns, and/or mortars from Oerlikon, Madsen, and Solothurn. Each infantry division had 6 French Brandt 81 mm mortars and 6 Solothurn 20 mm autocannons. Some independent brigades and artillery regiments were equipped with Bofors 72 mm L/14, or Krupp 72 mm L/29 mountain guns. They were 24 Rheinmetall 150 mm L/32 sFH 18 howitzers (bought in 1934) and 24 Krupp 150 mm L/30 sFH 18 howitzers (bought in 1936).
Infantry uniforms were basically redesigned Zhongshan suits. Leg wrappings are standard for soldiers and officers alike since the primary mode of movement for NRA troops was by foot. The helmets were the most distinguishing characteristic of these divisions. From the moment German M35 helmets (standard issue for the Wehrmacht until late in the European theatre) rolled off the production lines in 1935, and until 1936, the NRA imported 315,000 of these helmets, each with the 12-ray sun emblem of the ROC on the sides. Other equipment included cloth shoes for soldiers, leather shoes for officers and leather boots for high-ranking officers. Every soldier was issued ammunition, ammunition pouch/harness, a water flask, combat knives, food bag, and a gas mask.
On the other hand, warlord forces varied greatly in terms of equipment and training. Some warlord troops were notoriously under-equipped, such as Shanxi's Dadao Teams and the Yunnanese army. Some however were highly professional forces with their own air force and navies. The quality of Guangxi's army was almost on par with the Central Army's, as the Guangzhou region was wealthy and the local army could afford foreign instructors and arms. The Muslim Ma clique to the Northwest was famed for its well-trained cavalry divisions.