Plans for national defence in the event of another war had been drawn up and reviewed at intervals throughout the 1920s and 1930s, but the Munich crisis in 1938 jolted the authorities into practical action. Construction of air raid shelters of various kinds began, more training was provided for ARP volunteers, sandbags were filled, gasmasks and identity papers issued, evacuation plans rehearsed. When Chamberlain returned from his talks with Hitler to announce 'peace in our time' the general relief was manifest, and many Londoners were glad to forget the recent emergency preparations. Others, including Home Office staff, treated the news as a purely temporary respite giving an opportunity to remedy some weak links, especially through the provision of more shelters, the recruitment of extra ARP wardens, and the rehearsal of emergency drills. Barrage balloons were hoisted, blackout preparations made. The Ministry of Home Security appointed Regional Commissioners to be responsible for Civil Defence throughout the country; London — 'Region 5' — had Sir Ernest Gowers and Admiral Sir Edward Evans. If desperate times came, they were empowered to take over civil government in their region, with near dictatorial powers. War began to seem unavoidable.

1939 Evacuation of mothers and children began on 1 September. On 3 September war was declared, but apart from an immediate false alarm, nothing much happened and the 'phoney war' began, when the only bombs were planted by the IRA, and there was widespread criticism of 'overpaid' and apparently idle firemen and air raid wardens. 'Enemy' aliens were interned. By Christmas many evacuees had drifted back to London. Food rationing began. The quiet spell lasted until the summer of 1940.

1940 The fall of Norway, Belgium, Holland and France heralded the 'fífth columnist' scare about foreign spies, quantities of civilian refugees, invasion fears, the setting up of the Home Guard, the arrival of large numbers of Allied and Colonial troops, and the aerial 'Battle of Britain', clearly viewed by suburban South Londoners in August. On 23 August came the start of the Blitz, building up to a terrible autumn of heavy, nightly raids. Mercifully, pessimistic official forecasts about gas attacks and extremely severe physical and psychiatric bomb casualties proved ill-founded, but London suffered greatly. A particularly destructive incendiary raid on the City on 29 December prompted new regulations about regular overnight fírewatching, and there was a terrible direct hit on Bank underground station in January 1941.

1941 The attacks became less regular for a while though there were dreadful incidents like the destruction of the Café de Paris in early March. March and April were very bad and on 10-11 May came the severest raid yet on London, during which the House of commons was almost destroyed. More prosaically clothing was put on ration at this time, and a scrap metal drive led to many London park and garden railings being removed.

1942 passed without major incident in London. The city grew shabbier there was campaign to encourage 'holidays at home', with entertainments of all kinds in the parks , to dissuade Londoners from unnecessary travel. Various shortages irritated the public, and rationing was extended. American troops arrived with money spend and an aura of Hollywood glamour. But a general sense of tedium set in as people coped with the restrictions of life and began to regard further bombings unlikely. Victory at El Alamein in October turned the tide of war in the Allies favour and boosted public morale. However, Allied bombing of Germany, and especially of Berlin, brought tit for tat raiding from early 1943.

1943 Shelterers caught up in the tragic accident at Bethnal Green tube station in March when 173 people were suffocated in a fall down the entrance stairs had hurried there precisely because they were expecting a reprisal raid after a heavy Allied attack on Berlin the night before. Spasmodic nocturnal and daylight raid continued throughout the year, including machine gun attacks on schools in London, in January thirty-eight children and six teachers died at an LCC school in Catford. The winter was very severe.

1944 Early in the year the German bombers returned for the 'LittleBlitz'. There were fourteen major raids between January and April with incendiaries the main threat. Housing stock suffered badly; among other varied targets were the Surrey Docks and the London Library. The strain of more than four years of war was beginning to tell on Londoners who felt that victory was very close and that they had suffered enough. Morale improved with a lull in air attacks during April and May and news of the successful D-Day landings in early June. But German revenge on London was expected, and duly came from 13 June with the Vls, pilotless planes known as ‘Doodlebugs’ that bumbled overhead, cut out and dropped with devastating effect. South London took the brunt of these attacks, with Croydon particularly badly hit. One of the most damaging VI attacks was on the Guards' Chapel during a service in June, killing 119 and injuring 102.

Another wave of evacuees left London at this time. Adjustment to the unnerving new menace was difficult, but at least people could hear the engine approaching and had a few moments in which to dive for cover. The V2 rockets, launched from September, gave no warning at all, could not be intercepted, and caused dreadful carnage like the hit on Smithfield market, and the destruction of New Cross Road Woolworths in December. Many V2s fell in East London and its suburbs, wiping out whole streets at once.

1945 The last V-weapons landed in March at a stage when victory was known to be very near. There was a gradual relaxation of blackout regulations. Londoners celebrated VE Day on 8 May and VJ Day on 14 August. In between. In July, came the General Election returning a Labour government. London settled down to a long period of postwar austerity and a very slow programme of rebuilding and restoration.