Outbreak in Europe.

World War I began in summer 1914 as a conflict among the five "Big Powers" of Europe: Austria-Hungary, Great Britain, France, Germany, and Russia. In the quarter century leading up to the war the animosities between these powers resulted in a series of entangling alliances. Great Britain and Germany had been locked in an arms race on the seas that fueled their distrust of one another. As early as 1894 Germany, Austria- Hungary, and Italy had formed the Triple Entente, while the French and Russians had concluded a Dual Alliance; by 1904 the British and French had solidified an alliance of their own. The assassination of Archduke Francis Ferdinand of Austria-Hungary by a Serbian nationalist on 28 June 1914 at Sarajevo was the spark that lit the tinder, setting in motion a series of hurried diplomatic maneuverings that failed to prevent...