World War I started in 1914 due to rising nationalism and tensions between powerful European nations that were allied with each other through a system of alliances. The immediate trigger was the assassination of Archduke Franz Ferdinand of Austria-Hungary by a Serbian nationalist. This caused Austria-Hungary to declare war on Serbia and triggered the complex system of alliances that drew other European powers into the war. The war was the first modern industrial war that resulted in massive casualties and new military technologies like tanks and airplanes. It ended in 1918 with the defeat of the Central Powers and the signing of the Treaty of Versailles, which imposed punitive terms on Germany.