Following the Russo-Japanese War, the Japanese Empire sought to expand its influence over the resource-rich region of Manchuria in northeast China. To exploit the areas natural resources, Japan began construction of the South Manchuria Railway, a symbol of Japans imperial goals in the region. When the railway was seemingly attacked during the Mukden Incident on September 18, 1931, Japan took complete control of the region and established its own puppet state. How did the Mukden incident occur, and what were the motivations behind it?Background to the Mukden IncidentExpress train on the South Manchurian Railway, 1929. Source: Wikimedia CommonsThe Mukden Incident occurred during a time and context when regional tensions between China and Japan were reaching their breaking point. As Japan had made considerable territorial gains from China over portions of Manchuria after the Sino-Japanese War (1894-1895) and the Russo-Japanese War (1904-1905), it sought to consolidate the region as a whole and absorb it into the Japanese Empire. The South Manchuria Railway, which Japan used to exploit the areas natural resources, was a source of heightened tensions between China and Japantensions that would eventually lead to war.While Japan encroached on its territory and built a railway to exploit one of its contested territories, China was battling severe domestic unrest. During the 1920s and early 1930s, Chinas inability to deal with the threat from Japan was exacerbated by the struggles among the numerous warlords, which weakened the nations central authority. Amidst the unrest, Japan saw a chance to further its interests in Manchuria and began legitimizing its territorial ambitions with a diplomatic smoke screen.The Japanese Empires need for resources to feed its expanding industrial machine increased regional tensions. The abundant natural resources of Manchuria proved irresistible, and Japan believed that dominance over the area was crucial to its future as an imperial power. As a result, the stage was set for conflict, with both sides desiring influence over the area but having no diplomatic solution.The Mukden Incident: What Happened on September 18, 1931Japanese experts inspect the scene of the railway sabotage on the South Manchurian Railway, 1931. Source: Wikimedia CommonsThe South Manchuria Railway was at the heart of the Mukden Incident. On September 18, 1931, just outside present-day Shenyang, an explosion occurred on the railway. However, the explosion was reportedly so small that a scheduled train passed over the damaged track without any difficulty. Although the damage was not extensive and nobody was killed by the blast, the Japanese military took it as an act of deliberate violence and aggression by the Chinese.Today, new evidence has come to light that the militaristic Kwantung Army Colonel Seishir Itagaki and Lieutenant Colonel Kanji Ishiwara of the Japanese Kwantung Army, the military force guarding Japans interest in Manchuria, had planned the bombing as a pretext for an invasion of Manchuria.While the incident did not significantly damage the South Manchuria Railway, it gave the Kwantung Army the justification it needed to invade Manchuria on a large scale.Moving quickly, the Japanese Kwantung Army seized Mukden and other key locations in Manchuria under the pretext that they were looking for those responsible for the explosion. Little resistance was put up by the Chinese forces, who were unprepared for a full-scale invasion and were taken by surprise. Japanese forces seized control of several strategic sites in a matter of days, and Japans occupation of Manchuria had officially begun.Immediate Aftermath: Military Actions and OccupationJapanese soldiers of 29th Regiment taking an offensive posture on the Mukden Little West Gate, 1931. Source: Wikimedia CommonsThe Japanese military soon consolidated their gains over the region and quickly took control over the strategic Manchurian towns of Changchun, Jilin, and Harbin. The ease with which Japan took control over Manchuria and the swift nature of the invasion led many to believe that the entire Mukden incident was known about well in advance, the actions of the Kwantung army suggested that Japan had been waiting for this chance to increase its territory in Manchuria for some time.The unprepared Chinese soldiers found it difficult to defend against the approaching Japanese forces, who swiftly defeated them in every major engagement. Moreover, lack of unity in the Chinese government significantly prevented Chiang Kai-sheks Nationalist Party (Kuomintang) from organizing a successful counter-offensive. As a result, Manchuria was occupied by the Japanese at lightning speed, and it soon became a de facto part of the Japanese Empire.The diplomatic fallout from Japans invasion of Manchuria was severe. Naturally, China strongly objected to the invasion and sought assistance from its allies. However, the international response was, at best, muted, with many countries unable to help as they faced their own domestic, political, and economic problems.International Reactions: The League of Nations and Global DiplomacyThe League of Nations, 1920. Source: National Library of NorwayThe League of Nations, founded to uphold world peace and security after World War I, took the lead in the international response to Japans invasion of Manchuria. In response to Chinas cry for international aid, the League of Nations sent the Lytton Commission to investigate the Mukden Incident. The commissions conclusions, released in October 1932, stated that there was no reason for Japans invasion and that the Mukden Incident was not an act of Chinese aggression.While the Lytton Report had shown the world that Japan was unjustified in its actions, the League of Nations was unable to enforce any significant sanctions on Japan. Instead, the League demanded that Japan withdraw troops from Manchuria and resolve the conflict diplomatically. In response, Japan left the League of Nations in 1933. The failure of the League to hold Japan responsible exposed the flaws in the international system and gave other nations with expansionist goals, such as Italy and Germany, more confidence.As it was not a member of the League of Nations, the United States formulated its own response to the Mukden Incident. Forgoing its isolationist attitude, the US announced the Stimson Doctrine, which stated that it would not recognize any territorial gains a foreign power had made by force. However, this policy had no real-world impact, and no substantial measures were enforced.Propaganda and Narrative ControlManchukuo propaganda poster. Source: Wikimedia CommonsThe Japanese government shaped the public view of the Mukden Incident through the extensive use of propaganda. A coordinated campaign portrayed the invasion of Manchuria as a necessary step that had to be taken in order to secure Japans regional security and national sovereignty. The narrative that the Japanese government put forward focused on the necessity of economic development and self-defense, and blamed China for mismanaging Manchuria.Japans propaganda succeeded in persuading people that the invasion was justified. The official narrative was bolstered by the government-controlled media, which portrayed Japan as the benevolent force bringing modernization to Manchuria, and the Chinese as the aggressors. This image struck a chord with a public already shaped by feelings of nationalism and a sense of duty to steer Asias progress.From the Chinese perspective, propaganda relied more heavily on the truth. They portrayed Japan as an aggressive foreign power. The government narrative emphasized the unfairness of the invasion and focused on how the Chinese were made to suffer while foreign powers did nothing. However, internal divisions within China made it more difficult to rally the nation around the official government narrative.The Manchukuo Puppet StatePu Yi Qing during the Manchukuo Period. Source: Wikimedia CommonsAfter their successful invasion of Manchuria, the Japanese Empire founded the puppet state of Manchukuo in 1932. The former Emperor of China, Pu Yi, who had been ousted from power, was made the leader of the nation, and Manchukuo was presented to the world as an independent nation with its own government, people, and identity. The reality was that Manchukuo was a Japanese invention used to give legitimacy to Japans control of the area.During this period, Japan heavily developed the infrastructure of Manchuria and began to exploit the regions natural resources to full effect. The construction of factories, roads, and railways changed the landscape of the regiona project that benefited Japan almost entirely. The local population was subjected to harsh violence under Japanese rule and saw little advantage from the rapid industrialization.Long-term Consequences: Prelude to Greater ConflictJapanese Navy troops during the Battle of Shanghai, 1937. Source: Brent Jones / Wikimedia CommonsThe Mukden Incident of 1931 and Japans invasion of Manchuria paved the way for further conflict both in the region and across Asia as a whole. The militarist forces of Japan, which had orchestrated the incident, were encouraged by their success and the apparent unwillingness of the international community to intervene. This confidence was devastating as it gave them further motivation to continue aggressive acts throughout Asia and eventually led to their attack against America at Pearl Harbor, which precipitated US entry into World War II. Moreover, nations that shared Japans goal of expansionism saw the League of Nations inaction as a green light to carry out their aggressive ambitions.The loss of Manchuria was a severe setback for China, both economically and ideologically. In response to the invasion, Chinese nationalism began to rise, a development that ultimately led to the Second Sino-Japanese War (1937-1945), which devastated China and led to long-lasting consequences for the nation.