London's Strategic Context and Preparations for War

Why London was an important target

London’s importance made it particularly vulnerable in the Second World War. With a population of over eight million, it was Britain’s largest city, the seat of national government and the home of the Royal Family at Buckingham Palace. As the seat of government, it was where national decisions directing Britain’s war effort were made. Attacking the capital could therefore threaten both the population and the functioning of government, as well as striking at a powerful symbol of the nation.

London was also a major port and industrial centre. Its port handled over a quarter of Britain’s imports, making the docks vital for bringing in food and other essential goods. The Royal, West India, Millwall, Surrey Commercial and St Katharine Docks formed part of the port area targeted by Germany. Disrupting docks and warehouses could interrupt supplies needed by civilians and the war effort.

Important industrial sites stood along the river and nearby. Woolwich Arsenal produced munitions, Beckton gasworks supplied gas, and the Ford factory at Dagenham produced military vehicles, including army lorries, RAF tractors and troop carriers. These were concrete reasons for attacking London: damage could reduce weapons production, transport and essential services. Homes stood close to docks and factories, so attacks on economic targets also endangered civilians.

Why German bombers could reach London

London’s position in south-east England placed it within range of Luftwaffe bombers based in occupied France. German aircraft also operated from bases in the Low Countries. Once France had fallen in 1940, Germany could use bases across the Channel to launch attacks on Britain.

The River Thames helped aircraft find their way towards the capital and its docks. Its distinctive winding course provided a navigational reference, especially when the river reflected moonlight. German bombers also used radio navigation aids. London was therefore not just a valuable target: its location and recognisable river made it accessible to attackers.

The government regarded London as the main likely target and feared that war would bring immediate bombing and poison-gas attacks. Preparations therefore had to address different dangers. Moving vulnerable people away could reduce the number exposed to attacks; shelters could provide protection for those who remained; gas masks were a precaution against chemical attack.

Evacuation: moving people away from danger

Evacuation meant moving people from vulnerable places into areas thought to be safer. Government plans were developed with the help of the London County Council (LCC). They aimed to move about 1.25 million people out of the capital into reception areas across the south of England, East Anglia and the Midlands.

Children were a major priority, but evacuation was not simply a movement of children. Mothers, including expectant mothers, and people with disabilities or serious health needs were also involved. Entire schools could move with their pupils and staff, helping children continue their education away from London.

Putting these plans into practice required cooperation between the authorities sending people away and those receiving them. Transport was only one part of the task: evacuees also needed accommodation, schooling and welfare support. Billeting meant arranging for evacuees to stay in accommodation, often with host households.

About 600,000 people actually left London in August–September 1939, considerably fewer than planned. Evacuation was voluntary, so families could choose whether to leave. Moving also created difficulties: some Londoners complained about unsuitable accommodation, while host communities sometimes struggled to adjust to the newcomers. Other school communities settled successfully and remained away for much of the war.

Why evacuation had to continue

Many evacuees had returned to London by Christmas 1939. During the Phoney War, the expected major bombing had not materialised, encouraging parents to believe that home was safe again. The absence of attacks did not mean the danger had disappeared.

Evacuation was consequently an ongoing safeguard rather than a single event. Further departures followed the fall of France in 1940, the beginning of the Blitz that autumn and the flying-bomb attacks in 1944. Its effectiveness depended not only on organising departures but also on whether people chose to leave and stay away.

Anderson shelters: protection close to home

For people remaining in London, an Anderson shelter offered protection near their home. Named after Sir John Anderson, it was made from curved, corrugated-steel sheets bolted together. It was sunk about three feet into the ground and covered with about eighteen inches of earth.

The shelter’s partly buried position and earth covering provided a protective barrier between its occupants and the effects of nearby bombing. It was a precaution, not a guarantee of safety in every attack.

Anderson shelters had practical limitations. A household needed enough outdoor space to install one, so people without suitable space were encouraged to use communal shelters. Conditions inside could also be cold, dark and cramped. Many shelters leaked, and the noise of falling bombs could be amplified inside. Providing a shelter therefore did not automatically make it comfortable or easy to use.

Gas masks and other precautions

Poison gas was feared as well as bombing. Gas masks began to be issued in 1938, and more than 44 million had been distributed across Britain by the outbreak of war in September 1939. This was a national figure, not the number distributed in London alone.

The government urged people to carry their masks at all times, although carrying one was not a legal requirement. A mask could only be readily available in an emergency if its owner had it nearby. During the Phoney War, many people stopped carrying theirs, showing how a period without attacks could weaken willingness to maintain precautions.

The blackout, enforced from 1 September 1939, addressed a different danger. Curtains, cardboard and paint prevented light escaping from buildings; street lights and illuminated signs were extinguished, and vehicle lights were dimmed. The aim was to make targets harder for enemy bombers to locate at night. However, darker streets also increased the danger of accidents.

Together, these preparations show the challenge of protecting a working capital city: the authorities had to organise large schemes, but their success also depended on households changing their daily behaviour.

London as a target

• Government: national capital and seat of government; Buckingham Palace was the Royal Family’s home.
• Port: handled over a quarter of Britain’s imports; attacking docks threatened food and essential supplies.
• Industry: Woolwich Arsenal supplied munitions; Beckton gasworks supplied gas; Ford at Dagenham produced military vehicles.
• Accessibility: south-east England was within range of bombers based in occupied France; the Thames helped navigation towards London and its docks.

Evacuation

• Government and LCC organised movement to reception areas in the south, East Anglia and the Midlands.
• Priority groups included children, mothers and vulnerable people; schools could move with their staff.
• Planned: about 1.25 million people. Actually left: about 600,000 in August–September 1939.
• Voluntary: many returned by Christmas during the Phoney War.
• Renewed in and responded to changing threats.