Why as the battle of britain a key victory for the allied powers?

The Battle of Britain prevented a German invasion of the British Is less, and bought much needed time for the Allies to rearm and reorganize. When the Allies went on the offensive in Western Europe in 1944, Great Britain was the jumping off point. Also, British bombers, joined in 1942 by American bombers, pounded Germany from English air bases. All of this was made possible by the Battle of Britain in 1940.