1000 RAF bombers target Cologne

30th May 1942: Operation Millennium, the largest bombing raid the world had yet seen, overwhelms the defences of a major German city and sees one Victoria Cross

Official British war art imagining a bombing raid on Cologne. The city's cathedral is clearly visible. It survived the war, despite being hit dozens of times by Allied bombs.

RAF Bomber Command’s shift to ‘area bombing’ had already wrought devastation on the the cities of Lubeck and Rostock. Their destruction had sufficiently disturbed the Nazis to see them launch the retaliatory ‘Baedecker’ raids on Britain’s historic cities. But the head of Bomber Command, Arthur ‘Bomber’ Harris¹ wanted to mount an even more shocking attack:

There remained the problem of the first-class target, the major industrial town round which the enemy was bound to concentrate effective and heavy defences. So far all that the Lubeck and Rostock attacks had proved was that we could saturate the passive defences of a town by concentration of attack; it remained to be seen whether the active and passive defences of a vital industrial area could be similarly overcome.

Avro Manchesters of No. 49 Squadron RAF line up with Avro Lancasters of No. 83 Squadron RAF for the cameras of the Royal Air Force Film Production Unit at Scampton, Lincolnshire. Viewed from under the starboard wing of Lancaster Mark I, R5626 'OL-O', of 83 Squadron.

In order to achieve this he planned to use a much larger number of bombers to overcome the defences of an industrial target. By scraping together all the available bombers in service, including a number from training establishments, he found more than a 1000 aircraft. It was a figure that would ensure that Operation Millennium got plenty of attention around the world.

‘Gentlemen, tonight you are taking part in what will probably be the most important raid of the entire war. In fact, it may well finish the war.’