1914 By misaelbetancourt Jun 28, 1914 Francis Ferdinand assassinated at Saravejo Jul 5, 1914 Kaiser William II promised German support for Austria against Serbia Jul 28, 1914 Austria declared war on Serbia Aug 1, 1914 Germany declared war on Russia Aug 3, 1914 Germany declared war on France and invaded Belgium. Germany had to implement the Schlieffen Plan. Aug 4, 1914 Britain declared war on Germany Aug 23, 1914 The BEF started its retreat from Mons. Germany invaded France. Aug 26, 1914 Russian army defeated at Tannenburg and Masurian Lakes Sep 6, 1914 Battle of the Marne started Oct 18, 1914 First Battle of Ypres Oct 29, 1914 Turkey entered the war on Germany’s side. Trench warfare started to dominate the Western Front