The Battle of Britain began. It was the first major military campaign fought entirely by the air forces of Britain and its Allies against the German Luftwaffe. The Luftwaffe launched their offensive in conjunction with an air and sea blockade.Their targets were centered on British coastal shipping convoys, ports, and shipping centres such as Portsmouth. By mid-August the Luftwaffe began attacking RAF airfields and infrastructure, as well as factories producing aircraft, and strategic infrastructure. Eventually the Luftwaffe turned their guns on the British civilians and began a massive bombing campaign (The Blitz) on coastal towns and cities. By early September, the city of London became the target. A great part of the city was bombed and left in a mass of smoldering rubble. The Blitz resulted in 43,000 civilians dead and up to 139,000 injured. The RAF suffered heavy casualties, a situation which was exacerbated by their inexperienced pilots. To offset these losses, the RAF called in reinforcements from their allies, comprising of 145 Poles, 127 New Zealanders, 112 Canadians, 88 Czechoslovaks, 10 Irish, 32 Australians, 28 Belgians, 25 South Africans, 13 French, 9 Americans, 3 Southern Rhodesians. Despite being outnumbered, the Royal Air Force and its Allies demonstrated their air superiority over the German air force and won the Battle on October 31, 1940. Victory in the Battle was assured largely due to the participation of the Polish Air Forces, in particular the famous No. 303 Polish Fighter Squadron, also called the Kosciuszko Squadron, which contained the largest number of ace pilots in the RAF. The 303 had the highest RAF kill score in the Battle of Britain. Commanders Witold Urbanowicz, Jan Zumbach, and Zdzisław Henneberg (just to name a few) were among the many heroic Polish commanders and pilots who fought for Britain. (Read about the Kosciuszko Squadron)
Jedwabne Pogrom was a massacre of 340 Jews from the village of Jedwabne, Poland. On this day, a group of at least 40 Polish males were involved, after being summoned in Jedwabne by the order of Mayor Marian Karolak, and German paramilitaries, called Ordnungspolizei. The SS, Gestapo and Einsatzgruppe forces were also complicit. They then rounded up the local Jews as well Jews who sought refuge from the nearby towns of Wizna and Kolno, and took the them to the town square where they were humiliated and beaten. Ultimately, the Jews were forced into a barn, killed and the barn set on fire with them in it. (These are the official findings of the Institute of National Remembrance, which "confirmed by the number of victims in the two graves, according to the estimate of the archeological and anthropological team participating in the exhumation," wrote prosecutor Radosław J. Ignatiew, who headed an investigation in 2000–2003 ordered by the Polish government..)
Himmler gave the order for sterilization experiments at Ravensbrueck: In a letter from SS-Obersturmbannführer Brandt to Prof. Clauberg, July 10, 1942, read as follows: " Today the Reich Leader SS (Himmler) charged me with transmitting to you his wish that you go to Ravensbrueck after you have had another talk with SS-Obergruppenführer Pohl and the camp physician of the women's concentration camp Ravensbrueck, in order to perform the sterilization of Jewesses according to your method... (source: Trials of War Criminals Before the Nuremberg Military Tribunals - Washington, U.S Govt. Print. Off., 1949-1953, Vol. I, p. 729)
Augustow Roundup: The Augustów roundup was a military operation against the Polish anti-communist partisans which occurred following the Soviet takeover of Poland. Soviet forces with the assistance of Polish communist units, conducted the roundup from July 10 to July 25, 1945 in Suwałki and Augustów region (Podlasie) of northern People's Republic of Poland. Out of 2,000 arrested by the Soviet forces, about 600 disappeared. They were presumed to have been executed and buried in an unknown location in Russia or Belarus. The Polish Institute of National Remembrance has declared the 1945 Augustów roundup "the largest crime committed by the Soviets on Polish lands after World War II". The crime has been called "second Katyn", in reference to the Katyn massacre in 1940, when the Soviet NKVD executed over 16,000 Polish officers, soldiers, and intelligentsia.