After France fell, the British government was certain that Germany’s next move would be against the United Kingdom. These fears were confirmed when British intelligence intercepted coded German radio transmissions that made it clear that an invasion of Britain was imminent. Preparations in Britain had long been under way, and aircraft, guns, and ammunition were arriving by ship from the United States on a regular basis, despite the constant threat of attack by German submarines. The British would rely upon air and naval power as their primary defense, as they knew that they would quickly lose the war if German troops set foot on British soil in large numbers.
As Britain braced itself, one of its immediate goals was to prevent the French navy from falling into German hands. As a result, Operation Catapult was put into action on July 3, 1940. A British naval force based in Gibraltar was ordered to Mers-el-Kebir, Algeria, where much of the remaining French navy had fled. The British offered the French crews a choice: they could sail immediately for Britain and join in the fight against Germany, hand their ships over to the British, allow the British to move the ships somewhere safe in the West Indies, or scuttle their fleet. The French crews refused all four options, leaving the British little choice but to fire upon their allies, destroying the ships and killing over 1,200 French sailors. French ships at several other locations, however, were seized without incident.
The German code name for its plan to conquer the United Kingdom was Operation Sea Lion. The operation began tentatively, as a series of probing bomber attacks against British ships in the English Channel and ports in southern England in early July 1940. In fact, Hitler was still debating whether to invade Britain or Russia first.
The first German bomber attack over the Channel came on July 10, 1940. Yet even as late as July 19, Hitler made a last-minute speech advocating peace with Britain, presumably trying to buy time. Britain ignored the appeal. Skirmishes over the Channel and coastal southern England continued into August, but the Royal Air Force only rarely came out to defend the ships in the channel, preferring to hold off until the German planes got closer to the mainland, nearer to the limit of their range. As a result, British shipping in the Channel suffered heavy damage, but the RAF was able to conserve pilots and planes for the coming battle.
In early August 1940, Hitler decided to begin massive bombing raids on air bases and military command posts in southern England, hoping to break Britain’s will. Germany would withhold any attempt at a ground invasion, however, until it was clear that air superiority could be gained over England. On August 13, which the German high command labeled “Eagle Day,” Germany sent more than 1,400 bombers and fighters across the English Channel. The Germans brought down only thirteen British fighters that day but lost more than three times as many of their own aircraft.
Over the next several days, the Germans continued to suffer comparatively heavy losses. While this gave British pilots a certain sense of optimism, the sheer numbers of planes the Germans sent meant that many bombers were still reaching their targets. Nevertheless, even after three weeks of incessant attacks, the RAF was still very much intact.
In early September 1940, Hitler directed the Luftwaffe to shift its focus to the major British cities, including London. The attacks began on September 7 and continued into May of the following year. At times, they continued day and night for weeks at a time without letup. Tens of thousands of Londoners lost their lives during this time, along with thousands of residents of other British cities. In the meantime, however, British bombers were also conducting nightly air raids on central Berlin.
Although this London Blitz continued, Hitler decided on September 17, 1940, to put his plan for an invasion of Britain on hold indefinitely. It was clear that air superiority over England would be difficult to attain. Instead, Hitler turned his attention to Russia.
The Battle of Britain marked the first turning point in the war, as it was the first time that German forces failed to achieve a major goal. The Royal Air Force’s strong and effective resistance caused Hitler to abandon the idea of invading Britain and to turn his attention to Russia. Although the Blitz continued to terrorize London and other cities for months to come, Britain no longer faced the threat of a ground invasion. It demonstrated to the world that with enough stubborn resistance, Hitler could be forced back.
The Battle of Britain was also the first time in history when air power alone decided the outcome of a major battle. Hitler knew that there was no way he could invade Britain on the ground without first gaining air superiority. Churchill and the British military leadership also knew that stopping the Luftwaffe would be the key to their survival. The German air attacks against Britain were massive, but their initial intensity could not be maintained if the Germans were consistently losing twice as many aircraft as the British. Indeed, by the battle’s end, Germany had lost 1,700 planes to 900 British planes.
The value of the new technology of radar was also effectively demonstrated for the first time. The British had built a net of radar stations along their coastline prior to the battle, and this system proved invaluable, as British controllers could see the enemy coming and scramble fighters in the right place at the right time. Radar also prevented the loss of large numbers of aircraft on the ground, as happened during the initial days of the invasion of France. Although the Germans made an effort to bomb radar stations early on, by mid-August they gave up this strategy, believing it ineffective. It was a major mistake.
Moreover, British pilots had a considerable advantage in fighting over their own turf. Whereas German pilots had limited time over their target areas before having to return home to refuel, British pilots could stay in the air longer and even return to base, refuel, and then resume the fight. Thus, the mere act of engaging the German planes, forcing them to expend fuel by diverting them from their course, meant that fewer bombs would reach intended targets. For both Britain and Germany, this air combat was a new kind of warfare, and each side’s strategies were experimental in nature.