Russia Declares War on Turkey
Because of the help given by Turkey to the German attack of Russia, Russia declared war on Turkey.
The Serbian army fought the Battle of Cer against the invading Austrians, beginning on 12 August, occupying defensive positions on the south side of the Drina and Sava rivers. Over the next two weeks Austrian attacks were thrown back with heavy losses, which marked the first major Allied victory of the war and dashed Austrian hopes of a swift victory. As a result, Austria had to keep sizable forces on the Serbian front, weakening its efforts against Russia.