Etymology
Before World War II, the war was also known as The Great War, The World War, or The War in Europe .In France and Belgium, it was sometimes referred to as La Guerre du Droit (the War for Justice) or La Guerre Pour la Civilization / de Oorlog tot de Beschaving (the War to Preserve Civilisation), especially on medals and commemorative monuments. The term used by official histories of the war in Britain and Canada is First World War, while American histories generally use the term ‘World War’ I.
The earliest known use of the term First World War appeared in September 1914 when German biologist and philosopher Ernst Haeckel said, "there is no doubt that the course and character of the feared 'European War'" ... will become the first world war in the full sense of the word."The terms World War I and First World War both became standard (in the United States and Britain respectively) beginning in about 1940 to 1942; before that, it was most commonly called The Great War.
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Background
Map of the participants in World War I: Allied Powers in green, Central Powersin orange, and neutral countries in grey
In the 19th Century, the major European powers had gone to great lengths to maintain a balance of power throughout Europe, resulting by 1900 in a complex network of political and military alliances throughout the continent.These had started in 1815, with the Holy Alliance between Prussia, Russia, and Austria. Then, in October 1873, German Chancellor Bismarck negotiated theLeague of the Three Emperors (German: Dreikaiserbund) between the monarchs of Austria–Hungary, Russia and Germany. This agreement failed because Austria–Hungary and Russia could not agree over Balkan policy, leaving Germany and Austria–Hungary in an alliance formed in 1879, called the Dual Alliance. This was seen as a method of countering Russian influence in the Balkans as theOttoman