Western Europe in 1914 consisted mainly of Germany, France, UK, with Eastern Europe divided among four empires. World War 1 began in 1914 after the assassination of Archduke Franz Ferdinand, heir to the Austro-Hungarian throne, by Serbian terrorists. The war ended in 1918 with the Treaty of Versailles that reduced Germany territorially and financially and led to the redrawing of boundaries based on language and ethnicity. The post-war Mandate system formally placed former Ottoman and German colonies under Western control as independent nations emerged, fueling nationalism in Germany and Turkey who lost significant land and sovereignty.