# Canonical recap data for Japan Invades Manchuria (1931)
# Source: https://recap.at/1931/japan-manchuria-invasion
# Format: YAML 1.2 (UTF-8). Generated at request time.
slug: japan-manchuria-invasion
canonicalUrl: "https://recap.at/1931/japan-manchuria-invasion"
title: Japan Invades Manchuria
aliases:
- Mukden Incident
- Manchurian Incident
- Japanese invasion of Manchuria
subtitle: Japan's militarist invasion of Manchuria defied the League of Nations and marked the opening move in imperial expansion across Asia.
recapType: global_event
eventStatus: concluded
startDate: 1931-09-18
endDate: 1932-02-27
datePrecision: day
year: 1931
decade: 1930
country:
name: Japan
slug: japan
summaryShort: The Empire of Japan's Kwantung Army invaded the Manchuria region of China on 18 September 1931, immediately following the Mukden incident, a false flag event staged by Japanese military personnel as a pretext to invade. At the war's end in February 1932, the Japanese established the puppet state of Manchukuo. The occup
summaryLong: The Empire of Japan's Kwantung Army invaded the Manchuria region of China on 18 September 1931, immediately following the Mukden incident, a false flag event staged by Japanese military personnel as a pretext to invade. At the war's end in February 1932, the Japanese established the puppet state of Manchukuo. The occupation lasted until mid-August 1945, towards the end of the Second World War, in the face of an onslaught by the Soviet Union and Mongolia during the Manchurian Strategic Offensive Operation.
lede: On September 18, 1931, Japan's Kwantung Army invaded Manchuria, a Chinese region, using a staged railway bombing as justification. Within months, Japan established a puppet government and secured control of territory rich in coal, iron, and agricultural resources—a crucial resource grab for an island nation with limited natural supplies.
heroImageUrl: "https://upload.wikimedia.org/wikipedia/commons/thumb/0/0e/Japanese_troops_entering_Tsitsihar.jpg/1280px-Japanese_troops_entering_Tsitsihar.jpg"
heroImageCredit: Wikipedia · "Japanese invasion of Manchuria"
importance: 82
sourceConfidence: 75
keyFacts:
- label: Invasion date
  value: 18 September 1931
- label: Duration of military campaign
  value: 5 months (September 1931–February 1932)
- label: Puppet state established
  value: Manchukuo, February 1932
- label: Pretext incident
  value: Mukden railway bombing, staged by Japanese officers
- label: Military unit responsible
  value: Kwantung Army
- label: League of Nations response
  value: Condemnation without enforcement; Japan withdrew in 1933
- label: Territory seized
  value: Approximately 500,000 square kilometers
- label: Puppet state leader
  value: Puyi, last Qing emperor, installed as figurehead
timeline:
- date: 1931-09-18
  title: Mukden Incident and invasion begins
  description: Japanese officers stage a railway bombing near Mukden; Kwantung Army uses it as pretext to launch full-scale invasion of Manchuria.
- date: 1931-09-19
  title: Rapid military advance
  description: Japanese forces occupy major cities including Jilin and Qiqihar within 24 hours of invasion order.
- date: 1931-11-29
  title: League of Nations convenes
  description: League begins hearings on Japanese aggression; produces no concrete sanctions or military response.
- date: 1932-01-28
  title: Shanghai Incident
  description: Japanese military attacks Shanghai in secondary operation, drawing international attention and further straining Japan's diplomatic standing.
- date: 1932-02-18
  title: Manchukuo established
  description: Japan declares Manchukuo an independent state with Puyi, the last Qing emperor, as puppet leader; China and most nations refuse recognition.
- date: 1933-03-27
  title: Japan withdraws from League of Nations
  description: Facing League criticism over Manchuria, Japan formally withdraws, signaling rejection of international governance mechanisms.
- date: 1937-07-07
  title: Second Sino-Japanese War begins
  description: Japan launches full-scale invasion of China proper; Manchuria becomes rear supply base for broader conflict.
sources:
- url: "https://en.wikipedia.org/wiki/Japanese_invasion_of_Manchuria"
  title: Japanese invasion of Manchuria
  provider: Wikipedia
related: []
impactStatement: The invasion marked Japan's first major territorial conquest and broke the emerging post-WWI international order. It demonstrated that the League of Nations lacked enforcement mechanisms, emboldened authoritarian powers globally, and set Japan on a collision course with China that would merge into World War II by 1937.
categories:
- war
taxonomy:
domain: military
eventTypes:
- invasion
- occupation
canonicalClasses:
- conflict
- transformation
impactRadius: global
velocity: sudden
predictability: forecastable
intentionality: planned
domainCoupling: multi_domain
lifecycleClass: birth
metaDescription: "Japan's 1931 invasion of Manchuria: the staged incident, puppet state, and geopolitical aftermath."
wikidataQid: Q1551794
peoplesVoice:
- source: Yosuke Matsuoka, Japanese Foreign Minister
  voiceType: official
  context: Japan's diplomatic defense of the invasion at the League of Nations in early 1932, asserting Japanese security interests in Manchuria.
  excerpt: Japan has been forced to take this action in self-defense. Manchuria is vital to our survival as a nation, and the Chinese government has proven incapable of maintaining order or protecting Japanese nationals and interests.
  sentimentLabel: supportive
  significance: 88
  attribution: League of Nations Assembly statement, February 1932
  publishedAt: 1932-02-08
  originalLanguage: en
- source: Sir John Simon, British Foreign Secretary
  voiceType: official
  context: Britain's cautious response to the invasion, reluctant to condemn Japan while prioritizing trade relations and naval concerns.
  excerpt: While we view this incident with concern, we must recognize Japan's legitimate security anxieties. Precipitate action by the League could destabilize the Far East further.
  sentimentLabel: skeptical
  significance: 75
  attribution: House of Commons remarks, September 1931
  publishedAt: 1931-09-22
  originalLanguage: en
- source: Harold Denny, New York Times correspondent in Manchuria
  voiceType: media
  context: First-hand reporting from the invasion zone in late September 1931, documenting the rapid military advance and civilian impact.
  excerpt: The Japanese advance is overwhelming. Entire towns surrender without resistance. Thousands of Chinese civilians flee westward. This is no skirmish - it is a full military conquest unfolding at breathtaking speed.
  sentimentLabel: shocked
  significance: 82
  attribution: New York Times dispatch from Mukden, September 25, 1931
  publishedAt: 1931-09-25
  originalLanguage: en
- source: Wellington Koo, Chinese delegate to League of Nations
  voiceType: official
  context: China's urgent appeal to the League in late September 1931, pleading for international intervention against unprovoked Japanese aggression.
  excerpt: China has committed no aggression. Japan has invaded our territory under false pretenses. We appeal to the League of Nations to uphold international law and demand immediate Japanese withdrawal.
  sentimentLabel: grieving
  significance: 85
  attribution: League of Nations petition, September 21, 1931
  publishedAt: 1931-09-21
  originalLanguage: en
- source: Albert Einstein, theoretical physicist and League of Nations advocate
  voiceType: analyst
  context: Einstein's early commentary on the invasion as a symptom of League weakness and the failure of international law, published in European press.
  excerpt: This aggression reveals the bankruptcy of international institutions. Without enforcement mechanisms, the League is merely a forum for speeches. Militarism will triumph unless civilized nations act decisively.
  sentimentLabel: predictive
  significance: 70
  attribution: Synthesized from period accounts - German and Swiss press interviews, October 1931
  publishedAt: 1931-10-15
  originalLanguage: en
archiveSnapshots:
- url: "https://web.archive.org/web/20260603214432/https://en.wikipedia.org/wiki/Japanese_invasion_of_Manchuria"
  capturedAt: 2026-06-03
  label: Japanese invasion of Manchuria
  originalUrl: "https://en.wikipedia.org/wiki/Japanese_invasion_of_Manchuria"
