On August 23, 1939, the German Foreign Minister Joachim von Ribbentrop and his Soviet counterpart, Vyacheslav Molotov signed a non-aggression pact whereby neither party would ally itself with anyone who attacked the other party and both gave a guarantee of non-beligerance towards each other. It further came to light only in 1989 that the agreement was modified on September 18, 1939 and provided for the Soviets to annex the Baltic Republics of Estonia, Latvia and Lithuania, portions of Romania and portions of Finland in exchange for giving up more Polish territory to Germany.
Although the pact would unravel when the Nazis invaded the Soviet Union on June 22, 1941, in September of 1939, it provided Hitler with the one guarantee he desperately needed so he could invade Poland without fear of having both the Western Allies and the Soviets all declare war on Germany at the same time. This fear of having to fight a war on two fronts was a key concern of many senior Wehrmacht officers who were toying with the idea of overthrowing Hitler for fear that he was leading Germany to destruction. By signing the agreement with Stalin, with the stroke of a pen, Hitler removed one of their major concerns and further deflated the efforts of those who were warning that Hitler was going to bring on the destruction of Germany.
Thus on the morning of September 1, 1939, the Germans attacked eastward into Poland overland and simultaneously opened fire from a battleship, the Schleswig-Holstein at a place called Westerplatte in what was known at the time as the Free City of Danzig.
Westerplatte Memorial (at night)
At this point in the war, the German army was not the giant armored juggernaut that it would become. Nearly 1/3 of the armor that Germany used to attack Poland had been taken from the Czech Army. But it proved more than sufficient to take on the Poles who held out hope that the French and British would come to their aid. Nearly 85% of Germany’s armor was deployed in Poland yet even after declaring war on Germany on September 3, the French army did very little. A vigorous attack by the French into Germany would have made a difference but it was not to be.
The Polish Army and Air Force were terribly outmatched. By September 14, the Air Force all but ceased to exist. The Army did achieve some success in holding back the Germans but the fight was mostly a slow retreating battle towards the center of the country.
On September 17, Stalin ordered the Soviet Army to attack from the east in violation of a Soviet-Polish Non-Aggression Pact.. The Soviet government claimed that they were moving into Poland to “protect the Soviet minorities” since “Poland as a country had ceased to exist”. The Nazis had used this same ruse as an excuse to occupy the Sudetanland in October of 1938. 73 years later, Vladimir Puten made the same argument when he attacked The Crimea and Ukraine.
With the modified agreement between Hitler and Stalin signed on September 18, the Soviets and German’s divided Poland at the River Bug which today still stands as Poland’s eastern border.
The final battles in and around Warsaw concluded around September 29 while some Polish forces held out on the Hel Peninsula near Danzig on the Baltic Sea until October 2. The conquest of Poland had taken only a month.
As would become the usual case with invading German Armies, behind the army came the Einsatzgruppen. The Nazis, in the case of Poland, were interested in acquiring more living space or Lebensraum for the ethnic German people. The Poles were going to be worked to death or simply murdered and Hitler had just the right man for the job. The infamous Hans Frank was appointed the head of the civilian authority on October 3. It would be Frank who organized a reign of terror against the civilian population that led to the mass murder of Polish Jews and Poles alike. Of a pre-war population of 27 million, around 6 million were murdered (22%), 3 million of them were Jews. Had the Nazis won the war its likely that the Polish race would have ceased to exist. As it was, Frank would meet his end at the Nuremburg tribunals where he was convicted of various war crimes and executed.
The attacking Soviets behaved nearly as badly as the Nazis. Polish officers who surrendered to the Soviets were often summarily executed. When the fighting stopped, many civilians and military who fled east to escape the Nazis, were often deported to Siberia. In April and May of 1940, the Soviets murdered as many captured Polish Officers that they could get their hands on. Nearly 22,000 were summarily executed in the Katyn Forest near Smolensk.
Not everything went in Germany’s favor. As they invaded, three cryptologists slipped out of the country with a German enigma machine and the cyphers and equipment that they used to crack it. They made their way to England where they shared their knowledge with British code breakers including Alan Turing. Their work became the basis of the efforts at Bletchley Park to crack the German enigma codes giving the Allied armies a huge advantage. There is no doubt that these “Ultra” intercepts proved critical to the allied war effort and saved countless lives.
The Poles who had all been shipped off to Siberia by Stalin were eventually allowed to leave after the Nazi invasion of Russia. In exchange for Allied military assistance, Churchill demanded that Stalin release them. Upon their exit, they formed a Free Polish Army under the control of the Polish Government in Exile headquartered in London. Nearly 250,000 would fight in various campaigns and battles that included Polish pilots fighting during the Battle of Britain. The Polish Army fought in North Africa around Tokruk. They would be the ones to finally capture Monte Cassino in Italy. They fought in France after the invasion of Normandy where they tried to close the Falaise pocket to keep the German Army in Normandy from escaping and they participated in the fighting around Arnhem during Operation Market Garden.
After the war, the Free Polish Army was treated very poorly by the Allies, Against their desire, many were forced to return back to a Communist run Poland even though the allies knew that Stalin was going to mistreat them. Sure enough, Stalin had many of them executed upon their repatriation. He didn’t want any organized opposition to his handpicked post-war Communist Government.
A war that started over the invasion of Poland by a foreign country did not end in 1945. Liberation and freedom would only come some 50 years later with the fall of Communism.