The RAF had denied the Luftwaffe air superiority over the south of England. Now Hitler could not invade Britain and, on 17 September 1940, he postponed Operation Sealion.
Photo: Goering, sixth from right, and other German officers look out across the English Channel towards Dover on 1 July 1940. It was as close as they would get to invading. (IWM HU 1185)
The events of the 15th September.
From the Fighter Command control room in Uxbridge, Richard Holmes describes the RAF attacks on incoming German bombers.
German scepticism about the planned invasion of Britain
German naval officers describe their scepticism about the likely success of the planned invasion of Britain.
The resilience of Churchill and the British people
A summary of the 6 months from Germany's advance through Europe, to the end of 1940 and Britain's continued resistance to German bombing.
A.J.P. Taylor reveals why he thinks Hitler decided to invade Russia.
Why did Hitler insist on invading Russia? The renowned historian A.J.P. Taylor explains why he thinks the Fuhrer decided to attack his ally.
Hitler's attention turns away from Britain
Two days after the RAF's convincing victory over the Luftwaffe on 15 September, Hitler ordered Operation Sealion be postponed "until further notice". However, he insisted that the assembled invasion forces maintained a high state of preparedness.
Hitler's attention was now turning eastwards, and detailed planning began for the German invasion of the Soviet Union (Operation Barbarossa). Sealion was finally abandoned in February 1942.
Britain remains on a high state of alert
Winston Churchill, meanwhile, had been made aware via intercepted German radio messages that Hitler had ordered the dismantling of crucial air loading bays in Holland. So, whilst Churchill and his Chiefs of Staff now secretly deemed an invasion impossible, the rest of Britain remained on a high state of alert for potential invasion well into 1941.
Throughout the war, the British were able to de-code Germany's Enigma-encrypted communications. Information gleaned from these messages was vitally important and called Ultra - as in 'ultra secret'. Churchill called them his "golden eggs".
The debate about the likelihood of invasion
Some historians believe that the Germans were never serious about invading Britain, and had hoped to intimidate the government into negotiating or surrendering. There is also considerable debate about whether the invasion plan would have succeeded.
Even if Hermann Goering's Luftwaffe destroyed the RAF - necessary to ensure a successful offensive landing - the formidable Royal Navy still had to be contained. This was not a task the German admiralty relished as its fleet had suffered heavy losses in the Norway Campaign.
A lack of proper invasion barges would have meant improvised craft navigating across a lengthy stretch of water peppered with mines, whilst dodging British warships. This, followed by landings on a heavily defended coastline, would have been extremely difficult.
Disagreements also raged between the German army and navy over the size of the landing front. General Halder, Chief of the General Army Staff , at one point in negotiations exclaimed: 'I utterly reject the Navy's proposals [for landing on a narrow front]. I might just as well put the troops through a sausage machine!'.
The invasion plan was revised several times and, as early as 14 August, there were signs that Hitler was already backing away from a landing if the odds were too high. There were, he said, other ways of defeating Britain.
The bombing of British cities continues
An invasion may have been postponed, but the Luftwaffe now made British cities the front line of the war, and civilians were the troops. On the evening of 17 September itself, 300 German bombers stormed over the Channel. Harold Nicolson, the MP, wrote to his wife Vita Sackville-West: "I think we have avoided losing the war - but when I think how on earth we are going to win it, my imagination quails."