2.The first World War: was fought by two opposing alliances that included Various European countries, as well as the United States and Japan. 2.1The causes of the war: during the Period of uneasy peace in Europe at the end of the 19 century, there had been Various sources of tension.*France wanted to recover the region of Alsalce-Lorraine, which it had lost to the German Empire in 1871.*Between 1878 And 1908, the Austro-Hungarian Empire occupied and then annexed Bosnia-Herzegovina. This led to nationalist protests on the part of Serbians Living in Bosnia. It also angered Russia, Serbia´s traditional Ally.*Industrialised European countries expanded their empires and competed for Control of colonies, especially in North America.*Britain and Germany became Involved in a naval arms race. Both countries built a range of powerful new Battleships known as dreadnoughts. As a result of these disputes, two alliances Were established. On 28 of June 1914, Archduke FranzFerdinand, the heir to the Austro-Hungarian Empire, was Assassinated by a Serbian gunman in the Bosnian city of Sarajevo. His death triggered the sequence of events that led to the first world war: the Austro-Hungarian Empire declared war on Serbia, blaming the Serbs for the Archduke´s death.