The British officially recognise the battle 's duration as being from 10 July until 31 October 1940, which overlaps the period of large - scale night attacks known as the Blitz, that lasted from 7 September 1940 to 11 May 1941. German historians do not accept this subdivision and regard the battle as a single campaign lasting from July 1940 to June 1941, including the Blitz.
when did the battle of britain ww2 start
July 1940