Refugees near Warsaw during the 1939 German invasion of Poland. (Sign reads, 'Danger Zone -- Do Not Proceed.')
Refugees near Warsaw during the 1939 German invasion of Poland. (Sign reads, 'Danger Zone -- Do Not Proceed.')Hugo Jaeger—The LIFE Picture Collection/Getty Images
Refugees near Warsaw during the 1939 German invasion of Poland. (Sign reads, 'Danger Zone -- Do Not Proceed.')
Burned-out tank, Warsaw, 1939.
Adolf Hitler (right) prepares to fly to the Polish front, 1939.
Post-invasion Poland, 1939.
Unfinished Polish bombers, 1939.
Near Sochaczew during the German invasion of Poland, 1939.
Polish soldiers captured by Germans during the invasion of Poland, 1939.
Polish soldiers and a Red Cross nurse captured during the invasion of Poland, 1939.
Captured Polish soldiers, 1939.
German troops prepare for victory parade after the invasion of Poland, 1939.
German victory parade in Warsaw after the invasion of Poland, 1939. (Hitler is on platform, arm raised in Nazi salute.)
Adolf Hitler views victory parade in Warsaw after the German invasion of Poland, 1939.
Right to left, front row: Adjutant Wilhelm Brueckner, Luftwaffe fighter ace Adolf Galland, Gen. Albert Kesselring and Gen. Johannes Blaskowitz view the victory parade in Warsaw after the German invasion of Poland, 1939.
Head of the SS Heinrich Himmler (right), one of the chief architects of the Holocaust, speaks with an unidentified officer in Warsaw after German invasion of Poland, 1939.
Warsaw citizens buried their dead in parks and streets after the invasion of Poland, 1939.
Warsaw citizens buried their dead in parks and streets after the invasion of Poland, 1939.
Street scene following the German invasion of Poland, 1939.
German nationals prepare for repatriation during the invasion of Poland, 1939.
Polish farmers and peasants flee German military during invasion of their country, 1939.
Polish women clean captured Polish guns in Modlin Fortress, north of Warsaw, 1939.
Jewish women and children in Gostynin, Poland, after the German invasion, 1939.
Polish refugees, Warsaw, 1939.
Warsaw, 1939.
Near Modlin Fortress, Poland, 1939.
Near Modlin Fortress, Poland, 1939.
Scene in post-invasion Poland, 1939.
Poles stand beneath monument to Polish patriot, Jan Kiliński, 1939.
Near Sochaczew during the German invasion of Poland, 1939.
Near Danzig after the German conquest of Poland, 1939.
Flea market in post-invasion Warsaw Ghetto, 1940.
Near Warsaw, fall 1939; sign points to the battle front.
Refugees near Warsaw during the 1939 German invasion of Poland. (Sign reads, 'Danger Zone -- Do Not Proceed.')
Hugo Jaeger—The LIFE Picture Collection/Getty Images
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World War II Erupts: Color Photos From the Invasion of Poland, 1939

Oct 21, 2014

On Sept. 1, 1939, one week after Nazi Germany and the Soviet Union signed a non-aggression pact, more than a million German troops—along with 50,000 Slovakian soldiers—invaded Poland. Two weeks later, a half-million Russian troops attacked Poland from the east. After years of vague rumblings, explicit threats and open conjecture about the likelihood of a global conflict—in Europe, the Pacific and beyond—the Second World War had begun.

The ostensible aim of Germany's unprovoked assault, as publicly stated by Hitler and other prominent Nazi officials, was the pursuit of lebensraum—that is, territory deemed necessary for the expansion and survival of the Reich. But, of course, Hitler had no intention of ending his aggression at Poland's borders, and instead was launching a full-blown war against all of Europe. (On Sept. 3, both England and France declared war on Germany—but not on the USSR.)

The invasion—during which German troops, especially, drew virtually no distinction between civilians and military personnel and routinely attacked unarmed men, women and children—lasted just over a month. Caught between two massive, well-armed powers, the Polish army and its Air Force fought valiantly (contrary to legend, which has the Poles surrendering quickly, with barely a whimper). In the end, Poland's soldiers and aviators, fighting on two fronts, were simply overwhelmed.

In the weeks and months after the invasion, a German photographer named Hugo Jaeger traveled extensively throughout the vanquished country, making color pictures of the chaos and destruction that the five-week battle left in its wake. Here, on the 75th anniversary of the start of World War II, LIFE.com presents a series of Jaeger's pictures from Poland: portraits of a country subjugated not by one enemy, but by several.

In Jaeger's photos, meanwhile, we see early, unsettling evidence of the violence, unprecedented in its scope, that would soon be visited upon scores of countries and countless people around the globe, from the streets of London and the forests of Belgium to the North African desert and the sun-scorched islands of the South Pacific.

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