Britain and France declared war on Germany on 3 September. Under the security guarantees that had been given to Poland, that nation was supposed to fight a defensive campaign for only two weeks, at which time the Allies would counterattack from the west. That Allied offensive never occurred. By 14 September, the Germans had surrounded Warsaw. Three days later, Soviet forces invaded Poland from the east. The last Polish forces surrendered on 5 October.
There are many myths about Germany's so-called blitzkrieg campaign against Poland. The Polish air force was not destroyed on the ground on the first day of the war, and Polish horse cavalry units never mounted wave after wave of suicidal attacks against the German panzers. Nor was the campaign a walkover. The Poles held out for twice as long as they were expected to. In six weeks of fighting, the Germans suffered 50,000 casualties and lost 697 aircraft and 993 armored vehicles.
Under a secret clause of the German-Soviet Non-aggression Pact of August 1939, Germany and the Soviet Union participated in a fourth modern partition of Poland. The Soviets absorbed the eastern part of the country, including the great cultural centers of Lwow and Wilno. In the Soviet zone, 1.5 million Poles were deported to labor camps in Siberia. In a deliberate effort to exterminate the Polish intelligentsia and leadership classes, Soviets authorities transported thousands of captured Polish officers, including many reservists from universities and industry, to the Katyn Forest of eastern Poland and other locations, where they were executed and buried in anonymous mass graves.
Of the territory they occupied, the Germans annexed Pomerania, Posnania, and Silesia in the west. What was left became the General Government, under the harsh rule of Hans Frank. The Germans than began a campaign to liquidate the Jews of Poland and grind down the rest of the Poles. The Polish Jews were first herded into ghettos while the Germans built more than 2,000 concentration camps in Poland, including the industrial-scale death centers at Auschwitz, Birkenau, and Treblinka.
Several Poles, including many in the armed forces, managed to escape from the country before the Germans and Soviets tightened their viselike grip on it. Poles who escaped established a government-in-exile in London, with Wladyslaw Raczkiewicz as president and General Wladyslaw Sikorski as prime minister. In Poland, meanwhile, the Polish Resistance established the Armia Krajowa (AK, Home Army), which became the largest underground movement in Europe with 400,000 fighters.
Outside of Poland, the Polish army, air force, and navy reorganized themselves in Britain and continued the war. The Britain-based Polish army eventually fielded a corps in western Europe. After Germany attacked the Soviet Union in June 1941, the Soviets released several thousand Polish prisoners of war to establish another corps under General Wladyslaw Anders. The Polish II Corps was allowed to leave the Soviet Union by way of Persia and Egypt, and it eventually fought with distinction in North Africa and Italy.
Prior to the start of the war, Polish intelligence had managed to duplicate a German Enigma cipher machine. They turned over copies to both the French and British in July 1939, which was the starting point of the Allies' spectacular success with radio-derived communications intelligence. Later in the war, the intelligence service of the AK recovered a German V-2 rocket that had crashed in the Bug River after a test flight and sent the key components to London.
In 1943, the Soviets formed their own division of Polish troops to fight on the Eastern Front. That unit would eventually grow to field-army strength. But when the Germans later that year discovered the bodies of the Polish officers executed at the Katyn Forest and broadcast this news to the world, it opened a rift in Polish-Soviet relations that remained until the end of the Cold War.
As the Red Army slowly pushed the Germans from the Soviet Union and back to the west, the USSR's postwar intentions for Eastern Europe began to unfold. At the Allied Tehran Conference, British and U.S. leaders agreed to Soviet leader Josef Stalin's demands that the Soviet Union be allowed to keep the Polish territory taken in September 1939—in effect, the old Curzon Line established by the Allied governments in the peace settlement following World War I. After the war, Poland was partly compensated for its territorial losses in the east with a strip of German land in the west to the line of the Oder and Neisse Rivers. In July 1944, after the city of Lublin was liberated, the Soviets established their own Polish government, a direct rival to the one in London, which was now led by Stanislaw Mikolajczyk.
By 1 August 1944, the Red Army reached the right bank of the Vistula River opposite Warsaw. Armia Krajowa units in the city rose up against the Germans, anticipating Soviet support against the common enemy. The Soviets did nothing. Not only did they not help the AK, they refused landing rights on Soviet-controlled airfields for any Allied aircraft that might attempt aerial supply missions. The Poles fought on alone, street by street and house by house for 63 days, and in the end the Wehrmacht and the Waffen-Schutzstaffel (Waffen-SS) destroyed virtually the entire city. When the Germans finally withdrew from what was left of Warsaw, the Soviets moved across the river. The destruction of Warsaw eliminated the remaining political and military institutions in Poland still loyal to the London government and paved the way for a complete Soviet takeover. The final blows to a free Poland were delivered by the victorious Allies at the Yalta Conference. World War II ended, but Poland remained under the Soviet yoke until the very end of the Cold War more than 40 years later.
Poland suffered as heavily as any nation in the war, losing an estimated 38 percent of its national assets. The country lost 22 percent of its population—some 500,000 military personnel and 6 million civilians. Roughly half the Poles who died between 1939 and 1945 were Jews. Most of the approximately 5.4 million victims died in concentration camps and ghettos or by starvation, epidemic, or other causes resulting from the brutal occupation. One million of the survivors were war orphans, and another half million were invalids. David T. Zabecki
Coutouvidis, John, and Jaime Reynolds. Poland, 1939–1947. New York: Holmes and Meier, 1986.; Lukas, Richard C. Forgotten Holocaust: The Poles under German Occupation, 1939–1944. Lexington: University Press of Kentucky, 1986.; Prazmowska, Anita J. Britain and Poland 1939–1943: The Betrayed Ally. New York: Cambridge University Press, 1995.; Rossino, Alexander B. Hitler Strikes Poland: Blitzkrieg, Ideology, and Atrocity. Lawrence: University Press of Kansas, 2003.; Terry, Sarah Meiklejohn. Poland's Place in Europe: General Sikorski and the Origin of the Oder-Neisse Line, 1939–1943. Princeton, NJ: Princeton University Press, 1992.
David T. Zabecki