This is a History Extra production.

In the summer of 1940, the skies over Britain filled with the sound of engines and strafing.

The Battle of Britain saw the REF and the Luftwaffe go head to head in a fight for air dominance.

And for the British pilots, the objective could not have been more critical,

to protect their nation from the threat of Nazi invasion.

But were the British really the plucky underdogs in this fight?

And could Germany really have invaded if they had won the air battle over Britain?

Well, in today's episode, we're exploring those questions in the first episode of a five-part series

on the greatest battles of World

War II with the military historian James Holland. James is the author of books including

the Battle of Britain five months that changed history and also the co-founder of Chalk

History Festival of which we're a media partner. The festival runs from the 24th to the 30th of June this year,

and you can find out more at chalkfestival.com.

James was speaking to Rachel Dilling.

In 30 seconds, James, can you tell me why you've nominated the Battle of Britain

for this list of greatest

battles of the Second World War? Yeah, because it's one of the big moments. I mean, if

Britain had been defeated in 1940, it's game over. It's only because Britain holds out in

1940 that Hitler is forced to turn to the Soviet Union early because he can't afford to fight a war on two fronts.

He knows that America is waiting in the wings, that Britain is still holding out.

And obviously, the invasion of the Soviet Union is an absolute catastrophe for Nazi Germany.

And that's all because Hitler doesn't win against Britain in the summer of 1940.

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