World War I began as a local European war between Austria-Hungary and Serbia on July 28, 1914; was transformed into a general European struggle by declaration of war against Russia on August 1, 1914; and eventually became a global war involving 32 nations. It lasted from 1914 to 1918. Twenty-eight of these nations, known as the Allies and the Associated Powers, and including Great Britain, France, Russia, Italy, and the United States, opposed the coalition known as the Central Powers, consisting of Germany, Austria-Hungary, Turkey, and Bulgaria. The immediate cause of the war between Austria-Hungary and Serbia was the assassination on June 28, 1914, at Sarajevo in Bosnia (then part of the Austro-Hungarian Empire; now in Bosnia and Herzegovina), of Archduke Francis Ferdinand, heir-presumptive to the Austrian and Hungarian thrones, by Gavrilo Princip, a Serb nationalist. The fundamental causes of the conflict, however, were rooted deeply in the European history of the previous century, particularly in the political and economic policies that prevailed on the Continent after 1871, the year that marked the emergence of Germany as a great world power. The underlying causes of World War I were the spirit of nationalism that existed in Europe throughout the 19th and into the 20th century, the political and economic rivalry among the nations, and the establishment and maintenance in Europe after 1871 of large armaments and two hostile military alliances.