War is declared
Hitler now boosted by his earlier successes, signed a non-aggression agreement with Soviet Russia. On 1 Sept 1939, he went ahead with his invasion of Poland, confident that the British and French were unlikely to make good their guarantees to Poland. However he miscalculated and the British and French Governments issued an ultimatum to Germany to halt their attack. This ultimatum expired at 11am on 3 Sept 1939 and Britain was once more at war.
Hitler’s troops rapidly invaded Norway, Denmark, Holland, Belgium and France. Italy, in alliance with Germany, threatened British interests in the Mediterranean Sea and North Africa.
British forces were unable to halt the Germans in Northern France, and had to be rescued from Dunkirk. Hitler threatened to invade Britain, and his air force – the Luftwaffe – made many attacks across the skies of Kent. Britain and the Commonwealth countries were very much alone.