At the outbreak of World War I in August 1914, "Wettin" was mobilized into IV Battle Squadron under the command of "VAdm" Ehrhard Schmidt. IV Squadron also included her four sister ships and the battleships and . On 26 August, the ships were sent to rescue the stranded light cruiser , which had run aground off the island of Odensholm in the eastern Baltic, but the cruiser was scuttled by her crew before the relief force arrived. "Wettin" and the rest of the squadron returned to Bornholm that day. Starting on 3 September, IV Squadron, assisted by "Blücher", conducted a sweep into the Baltic. The operation lasted until 9 September but failed to bring Russian naval units to battle.