RAF Northolt opened in May 1915 as a base for the new Royal Flying Corps, with its aircraft flying defensive patrols against the German Zeppelins. In the 1930s, RAF Northolt was the first station to operate the Hurricane.
During the Battle of Britain it was the site of a Sector Operations Room and Staff, and the following Squadrons were based here during the Battle:
* No 609 Squadron from 19 May 1940
* No 257 Squadron from 4 July 1940
* No 303 Squadron from 22 July 1940
* No 43 Squadron from 23 July 1940 to 1 August 1940
* No 1 Squadron RCAF from 1 August 1940
* No 401 Squadron RCAF from Mid-August 1940
* No 615 Squadron from 10 October 1940
* No 302 Squadron from 11 October 1940
264 Squadron was also stationed here for a while, flying the doomed Boulton Paul Defiants. 303 (Polish) Squadron clocked up the highest allied scores during the Battle, with Czech Sergeant Josef Frantisek, becoming the highest scorer of the Battle. He is buried at Northolt. He shot down 17 enemy fighters in a 30 day period before crashing through tiredness and dying at the age of 24.