German military strategy - based on the Schlieffen Plan - was predicated on the idea of avoiding a 'two-front war' in the east and the west by first rapidly defeating France and then turning the full might of the German army against Russia.

From the outset, the First World War was a global conflict. The very first engagement of the war took place in West Africa, where British forces from the Gold Coast colony occupied the neighbouring German-owned territory of Togoland. During the autumn of 1914, Britain co-operated with Japan, which had declared war on Germany on 23 August, to ensure that it gained control of the German stronghold of Tsingtau on the eastern coast of China.

By the end of 1914, the two sides in the conflict could each claim the services of millions of soldiers from a total of six empires. The Triple Entente of Britain, France and Russia was pitted against the triumvirate known as the Central Powers: Germany, Austria-Hungary and Turkey (the latter had declared war on the Entente on 29 October). British and Indian troops were immediately dispatched to the eastern Turkish province of Mesopotamia to instigate what was widely expected to be the rapid disintegration of the Ottoman empire.

The war was evidently not going to be 'over by Christmas', as so many had initially thought. The extraordinary but brief - and unofficial - truce between British and German soldiers on the Western Front on Christmas Day 1914 could not mask the increasingly harsh intensity of the conflict.

The first British civilian casualties of the war were caused by German naval attacks on Scarborough, Whitby and Hartlepool on the north-east coast on 16 December. Allegations of German atrocities against civilians and captured Allied soldiers in Belgium were beginning to surface. Conditions in the trenches became increasingly desperate over the winter months. In the first five months of warfare alone, 300,000 Frenchmen had been killed - a figure greater than the total number of British war dead during the Second World War.

The following references give an idea of the sources held by The National Archives on the subject of this chapter. These documents can be seen on site at The National Archives.