It all began on August 24th 1940. A German plane meant to bomb British airfields missed its target and bombed London. Thinking this was deliberate, Churchill ordered the RAF to bomb the German capital city, Berlin.
Hitler, in a rage, ordered the Lufwaffe to change plan and to drop their bombs on British cities.
This time of city bombing, which started in early September 1940 and went on for nearly nine months, was known as 'the Blitz'.