The Blitz

The Blitz opened against London on 7 September 1940. For the next two months the capital remained the Luftwaffe's principal target, with raids arriving night after night from bases in France and the Low Countries. From November, the attack widened. Coventry, Birmingham, Bristol, Liverpool, Manchester, Sheffield and other industrial centres were struck in heavy raids. In February 1941 German orders placed greater emphasis on ports, bringing repeated attacks on Liverpool, Plymouth, Portsmouth, Swansea, Belfast and Clydeside.

Distance shaped every raid. Bombers leaving northern France crossed the Channel before spreading across routes that could extend hundreds of miles into Britain. At night, crews had few visible landmarks. Darkness, cloud and blackout obscured the ground, while navigation errors could carry a formation far from its intended target.

German radio-navigation systems helped crews find cities beyond the coast. Knickebein and later systems transmitted signals from continental Europe that gave bombers a line to follow toward the target. Those signals stretched across Britain long before the aircraft arrived.

On 7 September 1940, German bombers turned in strength against London after weeks of attacks on Fighter Command's airfields and sector stations. German commanders expected the capital to draw RAF fighters into a large battle while attacks on docks and industry damaged Britain's ability to continue the war. The change relieved some of the pressure on Fighter Command's southern bases at a critical point in the Battle of Britain.

Daylight losses soon pushed the bombing campaign increasingly into darkness. Britain had warning from radar and the Observer Corps, but finding a bomber at night was much harder than detecting its approach. Early Blenheim and Defiant night fighters achieved little. During the winter of 1940–41, Bristol Beaufighters carrying airborne interception radar began entering service, while new Ground Controlled Interception stations guided them close enough to make contact.

Civil defence presented another set of decisions. The government had distributed more than two million Anderson shelters by September 1940, yet many Londoners sought deeper protection in Underground stations. Officials initially resisted widespread use of the Tube, fearing disruption to transport and the growth of what they called a "deep shelter mentality." Londoners continued going underground, and by October the government formally permitted night sheltering in stations while retaining them for daytime transport.

The Luftwaffe entered the Blitz with medium bombers developed during the rapid expansion of the 1930s. Heinkel He 111s, Dornier Do 17s and Junkers Ju 88s could strike Britain from continental bases, but their bomb loads and defensive armament imposed limits during a sustained strategic campaign. As daylight losses mounted, darkness offered greater protection and allowed the bombing to continue deep into Britain.

British night defence developed while the Blitz was already underway. The Bristol Beaufighter combined speed, heavy cannon armament and AI Mk IV airborne radar. Ground controllers using the new GCI network guided fighters toward approaching bombers, after which the aircraft's own radar operator could take over the interception. By the spring of 1941, these elements were beginning to form an effective night-fighter system.

Most civilians experienced the air war through much simpler equipment. Anderson shelters stood in millions of gardens. From January 1941, Morrison shelters provided an indoor alternative for homes without suitable outside space. Wardens enforced blackout regulations, rescue parties searched damaged buildings and firefighters worked through incendiary raids that could ignite hundreds or thousands of separate fires.

The machines of the Blitz ranged from bombers and radar sets to corrugated steel shelters, sirens, searchlights and fire pumps. Together they show how the campaign reached far beyond the aircraft overhead.

The Blitz killed more British civilians than the British armed forces lost in any single year of the war until 1944. It also failed. War production dipped and recovered within weeks in every city attacked, and the campaign ended not because it was defeated but because the aircraft were needed in Russia.

The proportional figures matter more than the totals. London absorbed roughly half the dead across a population of eight million. Clydebank, a town of about 47,000, lost around 528 people in two nights and had perhaps 7 houses in the whole burgh left undamaged.

The official record is Basil Collier's The Defence of the United Kingdom, in the British official history series, with Terence O'Brien's civil defence volume alongside it. R. V. Jones's Most Secret War is the account of the radio beam intelligence by the man who ran it, written from the papers and unusually candid about what he got wrong.

The Imperial War Museums hold the photographic and film record and the Mass Observation archive at Sussex holds the contemporary record of what people actually said, which differs in useful ways from what the newsreels reported. Local figures for Coventry, Clydebank, Belfast and Liverpool come from the city and county archives rather than from national totals.