Publicity for the British First World War film For the Empire included the slogan: 'Damn the cost, we must win this war.' Yet, for both the victors and the vanquished, the material and human cost of the conflict was devastating.

In economic terms, the First World War - fought at an estimated cost of $208 billion - caused the greatest global depression of the 20th century. Debts accrued by all of the major combatants, with the notable exception of the USA, stalked the post-war economic world. Unemployment was rife. Inflation dramatically increased the cost of living - most famously in Weimar Germany, where hyperinflation meant that, by December 1923, a loaf of bread cost 428 billion marks. The First World War abruptly ended a period of relative economic prosperity, replacing it with two decades of economic misery.

To these figures must be added the 15 million men who were crippled by their service in the First World War. In Germany alone, 2.7 million soldiers returned home with permanent disabilities. Only 800,000 of them received invalidity pensions. The ongoing cost of the war can be seen in the fact that, in Britain during the late 1930s, 639,000 ex-soldiers and officers were still drawing disability pensions. This figure includes 65,000 men whose disabilities were not physical but mental. Some servicemen were so traumatised by their experiences in the First World War that they spent the rest of their lives in hospital.

The First World War also created a series of refugee crises, as the conflict forced whole populations - Armenians, Belgians, and Jews in Russia's Polish provinces - to flee from their homes to safer areas. The end of the war promised little better, creating a muddled legacy of displaced peoples throughout central and eastern Europe.

Post-war peace settlements in the Balkans and Anatolia, for example, led to the 'repatriation' of 1.2 million Greeks and 500,000 Turks. The truncation of German territory in Europe left roughly 9.5 million German speakers living outside the boundaries of the Weimar republic after the war. Many of the issues associated most readily with the Second World War - pogroms, refugee crises, forced transfers of populations, and genocide - had, in fact, already emerged in the First World War.