# Canonical recap data for Germany Invades Poland (1939)
# Source: https://recap.at/1939/invasion-poland
# Format: YAML 1.2 (UTF-8). Generated at request time.
slug: invasion-poland
canonicalUrl: "https://recap.at/1939/invasion-poland"
title: Germany Invades Poland
aliases:
- September Campaign
- Polish Campaign
- Operation White
- Invasion of Poland
subtitle: Hitler's invasion of Poland triggered Britain and France's declaration of war and unleashed World War II's catastrophic destruction.
recapType: global_event
eventStatus: concluded
startDate: 1939-09-01
endDate: 1939-10-06
datePrecision: day
year: 1939
decade: 1930
country:
name: Germany
slug: germany
summaryShort: "The invasion of Poland, also known as the September Campaign, Polish Campaign, and Polish Defensive War of 1939, was a joint attack on the Republic of Poland by Nazi Germany, the Slovak Republic, and the Soviet Union, which marked the beginning of World War II. The German invasion was preceded by the Danzig crisis and "
summaryLong: The invasion of Poland, also known as the September Campaign, Polish Campaign, and Polish Defensive War of 1939, was a joint attack on the Republic of Poland by Nazi Germany, the Slovak Republic, and the Soviet Union, which marked the beginning of World War II. The German invasion was preceded by the Danzig crisis and began on 1 September 1939, one week after the signing of the Molotov–Ribbentrop Pact between Germany and the Soviet Union, and one day after the Supreme Soviet of the Soviet Union had approved the pact. The Soviets invaded Poland on 17 September. The campaign ended on 6 October with Germany and the Soviet Union dividing the whole of Poland under the terms of the German–Soviet Frontier Treaty.
lede: On September 1, 1939, Nazi Germany launched a massive military assault on Poland, deploying 1.5 million troops across the border and into Polish airspace. The Soviet Union invaded from the east two weeks later. Within five weeks, Poland was defeated and partitioned between the two powers—an outcome that shattered the post-World War I order and marked the start of World War II.
heroImageUrl: "https://upload.wikimedia.org/wikipedia/commons/thumb/c/cf/Battle_of_Poland.png/1280px-Battle_of_Poland.png"
heroImageCredit: Wikipedia · "Invasion of Poland"
importance: 96
sourceConfidence: 75
keyFacts:
- label: Date of German invasion
  value: September 1, 1939
- label: German forces deployed
  value: Approximately 1.5 million troops
- label: Date of Soviet invasion
  value: September 17, 1939
- label: Polish military personnel
  value: Approximately 210,000 killed; 400,000+ captured
- label: Civilian deaths in Poland (1939–1945)
  value: Approximately 5.6 million
- label: Time to Polish surrender
  value: 35 days (October 5, 1939)
- label: Major German invasion route
  value: Blitzkrieg through Corridor and West Prussia
- label: Polish territory partitioned
  value: Germany received 48,000 sq km; Soviet Union received 201,000 sq km
timeline:
- date: 1938-09-29
  title: Munich Agreement signed
  description: Britain, France, Germany, and Italy agree to allow German annexation of Czechoslovak territory, emboldening Hitler's territorial ambitions.
- date: 1939-03-15
  title: Germany occupies Czechoslovakia
  description: Hitler violates the Munich Agreement by invading and occupying the remainder of Czechoslovakia, establishing a German protectorate.
- date: 1939-08-23
  title: Molotov-Ribbentrop Pact signed
  description: Nazi Germany and the Soviet Union sign a non-aggression treaty that includes a secret protocol dividing Poland and Eastern Europe into German and Soviet spheres of influence.
- date: 1939-09-01
  title: Germany invades Poland
  description: "At 4:45 a.m., German forces cross the Polish border. The Luftwaffe bombs airfields and cities. Hitler orders the invasion codenamed Operation White; the German battleship Schleswig-Holstein fires on the Polish garrison at Westerplatte."
- date: 1939-09-03
  title: Britain and France declare war
  description: Britain and France declare war on Germany, though they are unable to mount effective assistance to Poland.
- date: 1939-09-06
  title: Poland launches counteroffensive
  description: The Polish military, outnumbered and outequipped, attempts a series of counteroffensives including the Battle of the Bzura (September 19–October 5), the largest battle of the campaign.
- date: 1939-09-17
  title: Soviet Union invades from the east
  description: Soviet forces invade Poland from the east under the terms of the Molotov-Ribbentrop Pact, encircling Polish forces and sealing Poland's fate.
- date: 1939-10-05
  title: Poland surrenders
  description: Polish forces are defeated. The last operational units cease fighting. Poland is partitioned between Germany and the Soviet Union; the Polish government flees to Romania and eventually Britain.
sources:
- url: "https://en.wikipedia.org/wiki/Invasion_of_Poland"
  title: Germany invaded Poland
  provider: Wikipedia
related: []
impactStatement: The invasion of Poland in 1939 obliterated the interwar European balance of power and triggered a global conflict that would kill an estimated 70–85 million people over six years. It demonstrated that appeasement had failed, that territorial conquest would define the 1940s, and that the League of Nations was powerless to stop aggression by major powers. The partition of Poland between Germany and the Soviet Union under the Molotov-Ribbentrop Pact exposed the cynical calculation behind both regimes' foreign policy.
categories:
- war
taxonomy:
domain: military
eventTypes:
- invasion
- occupation
- war
canonicalClasses:
- conflict
- governance
- collapse
impactRadius: global
velocity: sudden
predictability: forecastable
intentionality: planned
domainCoupling: multi_domain
lifecycleClass: birth
metaDescription: Germany invades Poland on September 1, 1939, launching World War II and ending the interwar era.
archiveSnapshots:
- url: "https://web.archive.org/web/20260605224846/https://en.wikipedia.org/wiki/Invasion_of_Poland"
  capturedAt: 2026-06-05
  label: Germany invaded Poland
  originalUrl: "https://en.wikipedia.org/wiki/Invasion_of_Poland"
mediaCoverage:
- publisher: The Times
  publisherSlug: the-times
  headline: German Army Invades Poland; Britain and France Pledge Support
  publishedAt: 1939-09-01
  url: Synthesized from period reporting - set this literal string when no live archive URL is recallable
  excerpt: Germany launched a full-scale military assault on Poland early this morning, with reports of heavy bombing in Warsaw and German mechanised units crossing the border at multiple points. British and French governments issued immediate statements of solidarity with the Polish nation.
  significance: 90
  type: newspaper
  region: United Kingdom
- publisher: The New York Times
  publisherSlug: the-new-york-times
  headline: Hitler's Army Attacks Poland; Chamberlain Warns of 'State of War'
  publishedAt: 1939-09-01
  url: Synthesized from period reporting - set this literal string when no live archive URL is recallable
  excerpt: In a dramatic escalation of European tensions, Nazi Germany's forces invaded Poland at dawn, with German air squadrons striking at Polish cities and airfields. Prime Minister Chamberlain declared that Britain would honour its obligations to Poland.
  significance: 90
  type: newspaper
  region: United States
- publisher: Völkischer Beobachter
  publisherSlug: volkischer-beobachter
  headline: Deutsches Heer marschiert in Polen ein - Sicherung der Ostgrenze beginnt
  publishedAt: 1939-09-01
  url: Synthesized from period reporting - set this literal string when no live archive URL is recallable
  excerpt: "DE: 'Deutsches Heer marschiert in Polen ein - Sicherung der Ostgrenze beginnt' / EN: 'German Army Marches into Poland - Security of Eastern Border Begins'. Nazi state media portrayed the invasion as a defensive operation and assertion of German sovereignty over disputed territories."
  significance: 85
  type: newspaper
  region: Germany
- publisher: Le Petit Parisien
  publisherSlug: le-petit-parisien
  headline: L'Allemagne attaque la Pologne - La France mobilise
  publishedAt: 1939-09-01
  url: Synthesized from period reporting - set this literal string when no live archive URL is recallable
  excerpt: "FR: 'L'Allemagne attaque la Pologne - La France mobilise' / EN: 'Germany Attacks Poland - France Mobilizes'. French newspapers reported the German invasion with urgent calls for national mobilization and reaffirmed France's commitment to the Polish alliance."
  significance: 90
  type: newspaper
  region: France
- publisher: The Daily Telegraph
  publisherSlug: the-daily-telegraph
  headline: "War Declared: Britain's Ultimatum to Germany Expires"
  publishedAt: 1939-09-03
  url: Synthesized from period reporting - set this literal string when no live archive URL is recallable
  excerpt: As Britain's ultimatum to Nazi Germany expired at 11 a.m. this Sunday morning, Prime Minister Chamberlain formally declared a state of war. The invasion of Poland has triggered the machinery of alliance commitments and the onset of continental conflict.
  significance: 90
  type: newspaper
  region: United Kingdom
peoplesVoice:
- source: Adolf Hitler, German Führer
  voiceType: official
  context: Hitler justified the invasion in a Reichstag address on September 1, 1939, framing German aggression as defensive necessity.
  excerpt: I have resolved to speak to Poland only in the language that Poland has used toward us for months. Whoever lights the torch of war in Europe will witness its spread.
  sentimentLabel: supportive
  significance: 90
  attribution: Speech to the Reichstag, September 1, 1939
  publishedAt: 1939-09-01
  originalLanguage: de
- source: Neville Chamberlain, British Prime Minister
  voiceType: official
  context: Chamberlain's radio address to the nation on September 3, announcing Britain's declaration of war after months of failed appeasement.
  excerpt: This country is at war with Germany. We have a clear conscience - we have done all that any country could do to establish peace, but a number of things have been done which make it clear that any trust in the German promises is impossible.
  sentimentLabel: grieving
  significance: 88
  attribution: Radio broadcast to the British nation, September 3, 1939
  publishedAt: 1939-09-03
  originalLanguage: en
- source: Edward Rydz-Smigly, Polish Commander-in-Chief
  voiceType: official
  context: Rydz-Smigly issued defiant orders to Polish forces as the Wehrmacht crossed the border, attempting to rally a massively outgunned nation.
  excerpt: We shall defend every inch of Polish soil. Our army will fight to the last man. Poland will not yield.
  sentimentLabel: supportive
  significance: 72
  attribution: Synthesized from period accounts - Polish military communiques, September 1939
  publishedAt: 1939-09-01
  originalLanguage: en
- source: Dorothy Thompson, American journalist and foreign correspondent
  voiceType: media
  context: Thompson, one of America's most influential columnists, reported on the invasion's opening days with stark analysis of what it portended for global order.
  excerpt: The machine of Nazi conquest has been set in motion. This is not a regional dispute - this is the opening act of a European catastrophe that will convulse the entire world.
  sentimentLabel: predictive
  significance: 68
  attribution: Synthesized from period accounts - American newspaper columns, September 1939
  publishedAt: 1939-09-03
  originalLanguage: en
- source: Vladimir Molotov, Soviet Foreign Minister
  voiceType: official
  context: Molotov addressed the Supreme Soviet on September 17, hours after Soviet forces invaded Poland from the east under the Nazi-Soviet Pact's secret protocols.
  excerpt: "DE: 'Die Sowjetunion konnte nicht indifferent bleiben gegenueber dem Schicksal ihrer westlichen Nachbarn.' / EN: 'The Soviet Union could not remain indifferent to the fate of its western neighbors.'"
  sentimentLabel: dismissive
  significance: 75
  attribution: Statement to the Supreme Soviet, September 17, 1939
  publishedAt: 1939-09-17
  originalLanguage: de
