The Battle of Britain and the danger of invasion

The fall of France put England into straits not known since the days of the Armada: the analogy made by Churchill reflected Hitler's control of the Channel ports. From that position, Hitler would first knock England out by air attack and then launch a seaborne invasion; and, indeed, within ten days of France's accepting the German terms, the Luftwaffe started their raids and the Battle of Britain had begun. The danger of invasion was to dominate until October. But the intensity of the battle fluctuated; and there was no certainty about when Hitler intended to launch his invasion, though there was little doubt that he was planning one.

The air battle seemed to fall into three distinctive periods: the early days in July of lighter raids, the object of which was puzzling, for they were certainly not the ‘real thing’; the escalation of attack in early August with some heavy battles, but dying down by the end of the month with the odd plane ‘just buzzing’; and the culmination in September with the heaviest and most sustained attack. As the battle became more intense, so too did fears of an imminent invasion.

When the air raids began in early July, they were expected; and there were, as the air staff warned ‘grounds for expecting’ imminent invasion – ‘nothing … definite … [but] indications from a number of directions which pointed to [its] imminence … which would be insane to ignore’.