What was the effect of the german invasion of poland in 1939

The German invasion of Poland in 1939 caused the start of World War ll. When England and Germany signed the Munich Pact, Hitler "promised" not to invade any more countries, but when he took control of Poland, British Prime Minister Neville Chamberlain became angry that Hitler didn't follow through with his promise and World War ll began.

After heavy shelling and bombing, Warsaw surrendered to the Germans on September 27, 1939. Britain and France, standing by their guarantee of Poland's border, had declared war on Germany on September 3, 1939. The Soviet Union invaded eastern Poland on September 17, 1939.