On 15 July 1914, "Temeraire" was transferred to the 4th Battle Squadron and took part in a test mobilisation and fleet review between 17 and 20 July as part of the British response to the July Crisis. Arriving in Portland on 27 July, she was ordered to proceed with the rest of the Home Fleet to Scapa Flow two days later to safeguard the fleet from a possible German surprise attack. In August, following the outbreak of the First World War, the Home Fleet was reorganised as the Grand Fleet, and placed under the command of Admiral John Jellicoe. Most of it was briefly based (22 October to 3 November) at Lough Swilly, Ireland, while the defences at Scapa were strengthened. On the evening of 22 November, the Grand Fleet conducted a fruitless sweep in the southern half of the North Sea; "Temeraire" stood with the main body in support of Vice-Admiral David Beatty's 1st Battlecruiser Squadron. The fleet was back in port in Scapa Flow by 27 November. On 16 December, the Grand Fleet sortied during the German raid on Scarborough, Hartlepool and Whitby, but failed to make contact with the High Seas Fleet. "Temeraire" and the 4th BS conducted target practice north of the Hebrides on 24 December and then rendezvoused with the rest of the Grand Fleet for another sweep of the North Sea on 25–27 December.