After his election as Chancellor in 1933, Adolf Hitler immediately laid plans for rearmament and expansion of Germany's borders. In 1936 he violated the Treaty of Versailles by occupying the Rhineland – the demilitarized zone between Germany and France – and in 1938 seized Austria, inflicting violent anti-semitism against Vienna's large jewish community. These acts of aggression were largely ignored by Britain and the rest of Europe, who were unprepared and unwilling to go to war over the matter, prompting Hitler to set his sights on reclaiming the former German territory of Sudetenland – ruled by Czechoslavakia since 1919. He then threatened to invade Czechoslavakia unless Britain and France supported his claim.

In the diplomatic talks that followed, Hitler promised not to expand his territorial claims any further once Sudetenland was secured, and Britain and France agreed not to challenge his actions or go to war in support of Czechoslavakia's stand over the issue. Brandishing the signed Munich Agreement in September 1938, Prime Minister Neville Chamberlain told the British public it was 'peace for our time' but Hitler, after securing Sudetenland, reneged on the deal and in March 1939 invaded Czechoslavakia. In a desperate bid to prevent German expansion further eastwards, Chamberlain then agreed to a military commitment with Poland, but Hitler trumped him by signing a non-aggression pact with the Soviet Union – in effect allowing him to take Poland without Russian interference. This he did on 1 September 1939. The Anglo-French ultimatum calling for the withdrawal of German troops from Poland was then ignored, making war inevitable.

In truth, events in Europe during 1939 had already conditioned the British government to expect war, and on Friday 1 September general mobilisation was declared. Early that same day the evacuation began of thousands of school children away from cities most at risk from bombing, the mammoth task continuing throughout the weekend. Summer was now officially over of course, but in Bishop's Stortford and most of Britain the morning of Sunday 3 September was gloriously bright, warm and sunny and not at all the kind of day to be associated with bad news: but bad news there was.

At 10.00am the BBC told listeners to stand by for an announcement of national importance. Music and talk followed then at 11.15am Prime Minister Neville Chamberlain spoke to the waiting nation:

'I am speaking to you from the Cabinet Room at 10 Downing Street. This morning the British Ambassador in Berlin handed the German Government a final note stating that, unless we heard from them by eleven o'clock that they were prepared at once to withdraw their troops from Poland, a state of war would exist between us. I have to tell you now that no such undertaking has been received and that consequently this country is at war with Germany.' Chamberlain concluded his speech with the words, 'Now may God bless you all. May He defend the right. It is the evil things that we shall be fighting against, brute force, bad faith, injustice, oppression and persecution and against them I am certain that the right will prevail'.

Ten minutes after Chamberlain's broadcast, London's air raid sirens sounded sending thousands running for cover. It was though a false alarm, an unidentified aircraft passing over Kent and seemingly headed for the capital, was not the vanguard of a German attack but said to be a French plane whose pilot hadn't filed a flight plan.

*British people had been led to believe that a declaration of war would be followed by instant annihilation from the air. And a widely read book published during the Munich crisis, by JBS Haldane had forecast that the first German air attack might kill between fifty and one hundred thousand Londoners. Adding credence to this rather worrying prediction, the Committee of Imperial Defence's official estimate was that the opening assault from the air would last for two months, killing 600,000 people and injuring more than a million.

Such a scenario may now seem a little far-fetched, but to the people in 1939 it was just as believable as the threat of nuclear war was to the Cold War generation.

At noon the House of Commons sat for the first time on a Sunday since 1820. Debate about the war ensued, the assembled MPs then passing the National Service Armed Forces Bill stating that men aged between 18 and 41 were now liable for call up. As expected, Commonwealth countries including Canada, Australia and South Africa joined the declaration of war on Germany, and that afternoon Chamberlain formed his War Cabinet. At 6pm King George VI broadcast to the nation and Empire. Approximately an hour and a half later a German U-boat sank the SS Athenia just west of the Hebrides – an unarmed passenger liner travelling from Glasgow to Montreal, packed with over 300 Americans and Canadians and some 1000 European refugees. 112 people were killed.

At 8.30pm, France's leader Edouard Daladier broadcast to his nation that they were at war with Germany, and by 10pm that night thousands of British adult and child evacuees were adjusting to life in strange beds far from their own homes and loved ones.

On 5 September the United States of America proclaimed its neutrality.

None of these dramatic events were broadcast to the estimated 23,000 television sets owned at that time because BBC television had closed down on the day Poland was invaded. Drastic measures also meant that BBC radio would now be confined to a single, somewhat boring programme called the Home Service. For anyone who missed Chamberlain's broadcast, banner headlines in all the next day's national press left little doubt of what the future held.