Beginning of WWI Timeline By jin-gul1 Jun 28, 1914 Assassination of Franz Ferdinand Jul 5, 1914 Germany issued Austria their full support, the blank - cheque (carte blanche) Jul 23, 1914 Austria - Hungary sends Serbia an Ultimatum Jul 28, 1914 Austria – Hungary declares war on Serbia Jul 30, 1914 Russia announces their full support of Serbia Jul 31, 1914 Germany orders mobilization and sends ultimatum to Russia Aug 1, 1914 German mobilization and declaration of war on Russia Aug 2, 1914 French mobilization against Germany Aug 3, 1914 Germany declares war on France Aug 4, 1914 Britain declares war on Germany Aug 4, 1914 Germany invades Belgium Aug 6, 1914 Austria and Russia declare war on each other