During World War I, France was one of the Triple Entente powers allied against the Central Powers. Although fighting occurred worldwide, the bulk of the conflict in Europe occurred in Belgium, Luxembourg, France and Alsace-Lorraine along what came to be known as the Western Front, which consisted mainly of trench warfare. Specific operational, tactical, and strategic decisions by the high command on both sides of the conflict led to shifts in organizational capacity, as the French Army tried to respond to day-to-day fighting and long-term strategic and operational agendas. In particular, many problems caused the French high command to re-evaluate standard procedures, revise its command structures, re-equip the army, and to develop different tactical approaches. Background France had been the major power in Europe for most of the Early Modern Era: Louis XIV, in the seventeenth century, and Napoleon I in the nineteenth, had extended French power over most of Europe through skillful diplomacy and military prowess. The Treaty of Vienna in 1815 confirmed France as a European power broker. By the early 1850s, Prussian Chancellor Otto von Bismarck started a system of alliances designed to assert Prussian dominance over Central Europe. Bismarck's diplomatic maneuvering, and France's maladroit response to such crises as the Ems Dispatch and the Hohenzollern Candidature led to the French declaration of war in 1870. France's subsequent defeat in the Franco-Prussian War, including the loss of its army and the capture of its emperor at Sedan, the loss of territory, including Alsace-Lorraine, and the payment of heavy indemnities, left the French seething and placed the reacquisition of lost territory as a primary goal at the end of the 19th century; the defeat also ended French preeminence in Europe. Following German Unification, Bismarck attempted to isolate France diplomatically by befriending Austria-Hungary, Russia, Britain, and Italy. After 1870, the European powers began gaining settlements in Africa, with colonialism on that continent hitting its peak between 1895 and 1905. However, colonial disputes were only a minor cause of World War I, as most had been settled by 1914. Economic rivalry was not only a source for some of the colonial conflicts but also a minor cause for the start of World War I. For France, the rivalry was mostly with the rapidly industrializing Germany, which had seized the coal-rich region of Alsace-Lorraine in 1870, and later struggled with France over mineral-rich Morocco. Another cause of World War I was