[...] twenty years after regaining her independence, Poland was partitioned again between the Nazis and the Soviets. Since it is usually forgotten, it is good to stress that WW2 started when both Germany and the USSR, who were allies for two crucial years, invaded Poland.
For the next six years the Poles never gave up fighting. They fought in Poland and, with the British army, on many other fronts. They took part in the Battle of Britain, they fought in North Africa, Italy and elsewhere. There was, unlike what happened in most of conquered Europe, no Polish government collaborating with the Nazis. In continental Europe the Poles (with the Serbs) were Britain’s staunchest allies. When the war was over, instead of being given a seat in the UN Security Council, they were handed over to the Soviet Union.