War broke in 1914 due to a number of factors, and many of these dated back many years before the war. There were many things that contributed to the final war that was brought on by a certain catalyst. The arms race between Germany and Great Britain, the heated past of Germany and France, the tensions amongst the Balkan states, and between the Balkans and Austria-Hungary were all major contributing factors of the war. The feelings of nationalism in the Balkans increased tensions between them and Austria-Hungary, and Serbia was beginning to oppose them. Austria-Hungary feared this, and decided to invade, but alliances between bigger countries created heavy tensions. This was the basis of the triple alliance: Austria-Hungary, Germany, and later on Italy. This lead to conflict in that there were many other alliances throughout Europe which, in turn produced a chain of attacks. These alliances ultimately caused the conflict to escalate, as the two main alliances, The Triple Alliance, and The Triple Entente (Great Britain, France and Russia) were rivals, with Germany and France rivalling over Alsace Lorraine and Morocco, and Great Britain and Germany each trying to dominate the sea which, as an island, was Great Britain s main defence. These main European powers were in such conflict, which dated back many years. There had been friction between many of these powers such as: Germany and France from their ongoing wars, Serbia and Austria-Hungary from the nationalist tensions, and the rest of the Balkans in want of independence. Turkey and the Balkans also had war and conflict in their pasts. These tensions all mounted and were ignited when a Serbian terrorist movement, The Black Hand, assassinated the Austrian leader, Archduke Franz Ferdinand. The Austro-Hungarians attacked Serbia in outrage. The Russians, being allied with Serbia, attacked Austria-Hungary, which made Germany (Austro-Hungarian ally) attack Russia and France. Germany also invaded Belgium, which forced Great Britain to attack Germany. The United States joined at the request of Great Britain, when their force was down in the war. Imperialism and profits were hidden contributors to the war after the industrial revolution, when factory work became common, and when the lower-middle class of people began to make a living outside growing their own food. The nobles feared a peasant uprising, and so tensions grew between the middle class and the upper class. Because there was new hope for the lower-class citizens, they were eager to make their own profits, to become not so poor, and meant opposing the nobles in dominance of the county. These issues created huge tensions and secretly contributed to World War I.