Fought during the summer and early autumn of 1940, the Battle of Britain was one of the most crucial stages of the Second World War. But what if the RAF had been defeated?

Would a German invasion have soon followed? Would it have been successful? The University of Kent's Dr Charlie Hall predicts what could have happened next.

The Battle of Britain was one of the most significant and dramatic events of the Second World War.

Fought in the skies over Kent and southern England between the German Luftwaffe, which sought to secure air supremacy over the British Isles, as a necessary precursor to invasion, and the Royal Air Force.

The RAF was ultimately victorious and forced the Luftwaffe to change tactics, moving away from the targeting of airfields and aircraft factories and instead beginning the heavy bombardment of major cities, known as the Blitz.

Many see this as a key turning point in the war.

The Battle of Britain marked the first serious defeat Germany had suffered in the field and it ensured Britain would live on to take the fight to the Nazis in due course.

But what would have happened had the battle not resulted in a British victory?

Had the Luftwaffe achieved air supremacy over Britain, it would have allowed serious preparations for an invasion of the UK to proceed.

This would have been launched from sites throughout northern France and Belgium, with key beachheads established at four locations along the southern coast of England: between Folkestone and New Romney, between Rye and Hastings, between Bexhill and Eastbourne, and between Beachy Head and Brighton.

German paratroopers would have landed north of Hythe to seize the aerodrome at Lympne and bridge crossings over the Royal Military Canal.

This would have been followed by vicious fighting throughout Kent and Sussex as German forces sought to capture the key ports of Folkestone and Newhaven, so that more troops and supplies could be brought ashore in support of the invasion.

Had they been able to seize these vital entry points, an increasingly large German force would have then made its way towards London while the British Army, supported by the Home Guard, fought to prevent them from doing so.

This would have been made all the more terrifying with the Luftwaffe having full command of the air and being able to attack ground targets at will.

Key urban centres, such as Canterbury and Maidstone, would likely have suffered heavy bombardment and shelling, followed by intense street fighting.

It is, however, possible that German forces may have made efforts to avoid damaging significant cultural landmarks, such as Canterbury Cathedral.

Beyond these first objectives, it becomes very difficult to imagine what would have happened next.

If German military victories elsewhere in Europe during this period are anything to go by, it is quite possible that they would have made good progress towards London, but capturing the city itself would have posed a colossal challenge.

It is even harder to visualise what ultimate German victory in Britain would have looked like.

Britain may have surrendered and become a German ally, or it may have been divided in two, as France was, with an occupied south and an unoccupied north.

Churchill and his colleagues would have been removed and a British government may well have been formed under Oswald Mosley, the leader of the British Union of Fascists.

Rumours suggest that Edward VIII, who had abdicated in 1936 and had shown possible Nazi sympathies in the past, would have been returned to the throne, but this is highly unlikely.

However, it is also worth noting that, even with air supremacy assured, a seaborne invasion of Britain would have been enormously difficult, not least thanks to the size and power of the Royal Navy guarding the Channel.

Coastal defences in Kent and the tenacity of local defenders would have made it doubly challenging.

Instead, German forces, now unopposed in the air, might have opted for a more comprehensive bombing campaign, which, by focusing on ports and other logistical targets, may have knocked Britain out of the war through starvation and a lack of vital supplies.

In either case, with Britain defeated, American entry into the war against Germany would have become even less likely and German forces would have been free to throw more resources into the invasion of the Soviet Union, perhaps leading to a different outcome in that theatre.

As such, victory in the Battle of Britain ensured the nation and its empire could continue fighting at a critical moment, and could go on to build the Grand Alliance which eventually destroyed the Nazi regime.

This is the second of our What If features on KentOnline. Last week, we looked at what would have happened if Thomas Becket hadn't been murdered, and next Monday we'll explore what if the Romans hadn't arrived in Kent.

Dr Charlie Hall is lecturer in Modern European History at the University of Kent. His research focuses

on Britain’s relationship with the Third Reich, and British interpretations of Nazism from the Beer Hall Putsch to the present day.

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