This is a History Extra production.

On the 6th of June, 1944, the Allies began their long-awaited invasion of Nazi-occupied Europe.

After crossing the channel in the dead of night, paratroopers and glider infantry landed in rural Normandy,

while Allied ships attacked the nearby coastal defences, paving the way for troops to come ashore across five beaches.

By the end of the day, forever immortalized as D-Day, more than 150,000 men had arrived in northern France,

ready to start pushing deeper into Europe and deliver the fatal blow to Hitler's regime.

My name is John Borken, and over the course of three episodes, I'll be exploring D-Day by

land, air and sea, revealing how the invasion was planned and how it

unfolded. With the help of three leading experts, I'll also be telling the stories of some of the

people who served and looking at why 80 years on their action should be remembered.

In this first episode, you'll be hearing from the acclaimed author and military historian,

Saul David, about the role of the airborne forces on D-Day. I began my discussion with

Saul by asking him to summarize exactly what it was the men set out to achieve and why they were

so pivotal to the invasion's overall success. The Allied airborne operations were absolutely crucial to the success of D-Day,

and that was chiefly because the airborne forces, paratroopers and glider-borne infantry,

had the task of dropping and landing in France the night before the actual sea landings,

and their job was to protect both flanks of the Allied beachhead.

Now, if the airborne forces

had failed to achieve their various objectives, it would have left those flanks open to German

armoured counterattacks, which, in the worst case scenario, might have driven the invading

troops into the sea and caused the failure of Operation Overlord. This was the real fear of

General Eisenhower,

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