United Kingdom 1939 - 1940
At the dawn of 1939, the likelihood of another European war was growing ever greater. Germany had invaded, and then annexed, Austria in March 1938. In October that year, contrary to the Munich agreement, German troops occupied the Sudetenland which was part of Czechoslovakia.
In March 1939, Germany occupied the whole of Czechoslovakia, and war seemed inevitable. H.M. Government began to change its policy of appeasement, and full-scale rearmament of the British Armed Forces commenced (although it can be argued that some form of re-armament commenced in the mid-1930’s, contrary to popular belief). Plans were drawn up for the British Army to send an expeditionary force of two corps (each comprising two infantry divisions) to France at the outbreak of war. This was in anticipation of defending France in a similar manner to the circumstances of the Great War.
On 29 March 1939, the Secretary of State for War announced that the Territorial Army was to be increased in establishment from 130,000 to 170,000, and then doubled in numbers. Each of the existing first line Territorial Army units and formations were required to form duplicate (or second line) units and formations. Although the personnel came forward, equipment for them was scarce.
Conscription was introduced on 27 April 1939 for the first time in British peacetime history. The Military Training Act required all males to serve in the Armed Forces for six months on reaching their twentieth birthday. On completion of six months service, the conscripts were required to serve in the Territorial Army or Special Reserve. This measure had only just been instituted by the outbreak of war, with only one intake of 35,000 men called up on 15 July.
Germany invaded Poland on 1 September 1939, and in consequence, in accordance with Polish-British Common Defence Pact, the United Kingdom declared war on Germany with effect from 3 September 1939. The British Army had started mobilizing on 1 September, but was woefully ill-equipped and ill-prepared for war. Much of the strategy, tactics and equipment dated from the Great War. The first elements of the British Expeditionary Force left for France on 3 September 1939, just over twenty-five years since its predecessor had crossed the English Channel bound for war.