Poland engulfed
The Germans invaded western Poland on 1 September 1939. Two days later, Britain and France declared war on Germany. The Poles were overjoyed, confident that with British and French support the Germans could be beaten. Crowds of happy Poles swarmed around the British and French embassies in Warsaw to express their gratitude to their new allies.
On 17 September, Russian troops invaded eastern Poland, as had been agreed secretly in the pact signed between Hitler and the Russian leader, Stalin, in August. Poland was now faced with two enemies attacking on two fronts. By the end of September, Poland ceased to exist. The Russians took one half of Poland and the Germans the other.
British and French land forces in western Europe had scarcely fired a single shot and had stood by as the Polish state disappeared, even though France alone had 57 divisions on its German border facing just 32 German divisions. (A division, on average, numbered about 15,000 men.) An attack on Germany then, when most of its armed forces were involved in Poland, could have achieved remarkable success. But the French lacked the necessary aggressive spirit. By the end of September, the Germans had increased the number of divisions on the French-German border to over 100. The British Royal Air Force, however, did find time to drop 18 million leaflets over German cities, suggesting that Hitler was a bit of a scoundrel.
Neil Demarco: The era of the Second World War; Oxford University Press, 1993/2000, page 25