The Battle of Britain began on August 1940.
After the French collapsed under the Blitzkrieg and surrendered in June, the Germans were not exactly sure what to do next. Adolf Hitler (and the German people) believed the war was over and the Britons would come to terms very soon. Patriotic myth states that stubborn as they are, Albion refused to give in. In reality there was a considerable section of the public and politicians who believed it was time to negotiate with Hitler. Churchill, however, was the master of the Cabinet and would not contenance peace, putting Lord Halifax (one of the pro-peace members of the Cabinet) on the air to reject Hitler's terms.
More direct measures were thought of, but it was not until July that an invasion plan was prepared by the OKW (Armed Forces High Command), the operation was code-named Seelöwe (Sea-Lion). Invasion date was set for around mid-September, although the Navy stated that no specific date could be decided until the Luftwaffe controlled the air over the Channel. The plan was to land with 9 divisons by sea, plus another 2 by air in a narrow front around Dover. All preparations for that invasion were supposed to be made within just the time from mid-June to late-August (which was impossible). A lot of these preparations were very makeshift, like using and converting river barges for troop transport purposes, or using discarded aircraft engines for motorizing barges. Others were very well thought out, like swimming tanks or using snorkels on the heavier tanks so they could be landed further out on sea and march to land on the seabed. Hindsight suggests that the enitire operation was not seriously planned with actual execution in mind, especially when compared to Operation Barbarossa. Indeed Churchill did not take the invasion threat seriously, sending troops to Africa in the summer of 1940, but he was concerned over the potential air threat and energetic in securing resources for the RAF.
But before Seelöwe could begin the Luftwaffe had to destroy the British RAF - otherwise the ships for the sea invasion would have been destroyed by British aircraft.. Goering called his plans Adlerangriff (Eagle Attack), beginning on August 11 with Adlertag (Eagle Day). But even before this there was a month of attacks on Channel convoys and the RAF out over the water. This period of fighting was called Kanalkampf by the Germans.
The British were fully aware of the German goals, strategy, and often even tactics due to their ability to read the German Enigma cypher, which was used for most high-security german military radio communications. This fact, not revealed until the 1970's, was crucial in forming British tactics.
The Battle can be crudely divided into four sections:
- July - August 11 Kanalkampf
- August 12 - August 24 Adlerangriff
- August 25 - Sept 6 German's attack RAF planes and airfields almost exclusively. The critical period of the battle
- Sept 7 + London and other major cities are bombed.
Adlertag began with the Luftwaffe bombing ports, airfields, aircraft industries, radar installations, etc. Over the course of the next weeks, they flew 12,039 sorties and dropped over 11,000 tons of high explosive bombs and over 616 tons of incendiary bombs.
At first, the main targets for the German Luftwaffe were radar installations and airports, in an attempt to destroy (either on the ground, or in the air defending the ground targets) or render useless the British fighter planes. The attacks against the radar installations were not seen as very successful, and since the Germans underestimated the effectiveness of British radar, they soon stopped targeting radar installations. Thanks to radar and the intelligence from the decoded Enigma messages the RAF reacted very effectively to the German raids. Rather than sending up large numbers of fighters to meet German raids (and thus running the risk of of having all the planes on the ground for refuelling and repairs when another raid arrives), British commanders ordered that only a very few fighters up to meet each raid, harassing the German bombers enough to make accurate bombing very difficult and causing far more British losses than German.
Both sides suffered horribly, but British pilot losses were smaller since most of the fights were fought over British soil, whereas every German crew that had to bail out was lost to the German war effort.
Thanks to the seemingly endless numbers of planes the Germans had at their disposal, the British Fighter Command still began to lose this battle of attrition. A change came when Germany decided to switch to terror bombing. The first such raid on 7th of September was intended as revenge for the British attack on Berlin on 25th/26th August. Although the docks of London were the main target attacked, the British suffered 448 dead and more than 1,300 wounded.
Together with the change of targets came a change in strategy. The success in the Battle of Britain was no longer seen as prerequisite for Seelöwe, but was meant to be decisive in itself. Goering believed that the British would surrender as soon as the RAF was beaten. On 16th of September the Germans estimated British fighter strength to be no more than 300 planes, when they actually had 572 Spitfires and Hurricanes. But with the change of targets, British aircraft losses would decrease and the battered RAF would be able to rebuild.
On September 19th Operation Seelöwe was postponed indefinitely. But the battle of Britain was not over. From October 1940 until the beginning of Operation Barbarossa, the German attack on Russia in June 1941, almost 40,000 additional sorties were flown and more than 38,000 tons of high explosive bombs and more than 3,500 tons of incendiary bombs were dropped. Between August and September the RAF stated German losses at 1600 aircraft destroyed and over 500 probables, however despite most of the fighting occuring over land only 315 wrecks were identified. British Fighter Command lost between 900 and 1900 Hurricanes and Spitfires (depending on which figures you care to believe).
Overall the Battle of Britain was a British victory, although on a small scale compared to later battles it was significant, especially in increasing American anti-Nazi opinion. Although the Germans came very close to beating the RAF and thus setting the prerequisites for Seelöwe, the switch to terror strategy allowed the RAF to recuperate and to defend against the attacks. The terror strategy in itself could not force the British to surrender. Even though the Germans launched some spectacular attacks against important British industries, they could not destroy the British industrial potential.
Total British civilian losses from July to December 1940 were 23,002 dead and 32,138 wounded.