When the First World War broke out in August 1914, "Goliath" returned to full commission and was assigned to the 8th Battle Squadron, Channel Fleet, operating out of Devonport. She was sent to Loch Ewe as guard ship to defend the Grand Fleet anchorage, and then covered the landing of the Plymouth Marine Battalion at Ostend, Belgium on 25 August 1914. For this operation, she and three other battleships—, , and —a protected cruiser, and six destroyers escorted the troopships; at the same time, elements of the Grand Fleet attacked the German patrol line off Heligoland to occupy the German High Seas Fleet.