First World War By alinero Jun 28, 1914 assessination of Archduke Francis Ferdinand Jul 23, 1914 Austrian ultimatum to serbia Jul 28, 1914 austria declares war on serbia Jul 29, 1914 austria declares war on serbia Jul 29, 1914 russia mobilizes Jul 31, 1914 german ultimatum to russia Aug 1, 1914 germany declares war on russia Aug 3, 1914 germany declares war on france Aug 4, 1914 german troops invade belgium Aug 4, 1914 great britain declared war on germany
