in August and September 1914 into 1st Line (liable for overseas service) and 2nd Line (home service for those unable or unwilling to serve overseas) units. Later, a 3rd Line was formed to act as a reserve, providing trained replacements for the 1st and 2nd Line regiments. 1/1st, 1/2nd and 1/3rd Scottish Horse The 1st and 2nd Scottish Horse were expanded with the creation of the 3rd Regiment in August 1914 and the Scottish Horse Mounted Brigade was then formed with these three regiments in September 1914. By January 1915, the Scottish Horse Mounted Brigade was attached to the 63rd (2nd Northumbrian) Division on coastal defence duties in the UK. By August 1915 the regiments were ready for foreign service and took part in dismounted landings at Suvla Bay, Gallipoli on 2 September 1915, attached to 2nd Mounted Division. December 1915 saw the 1st, 2nd and 3rd Regiments evacuated from Gallipoli and moved to Egypt. Due to heavy casualties, the Scottish Horse Brigade was absorbed into 1st Dismounted Brigade on Suez Canal defences in February 1916. On 29 September 1916, the 1st and 2nd Regiments formed an infantry battalion. Just over two weeks later, on 15 October 1916, it became known as the 13th (Scottish Horse Yeomanry) Battalion, the Black Watch. The 13th (Scottish Horse Yeomanry) Battalion of The Black Watch was sent to fight in Salonika as part of the 81st Brigade in 27th Division. The 3rd Regiment was formed into the 26th (Scottish Horse) Squadron, the Machine Gun Corps and continued to serve in Egypt before being re-titled as a company and posted to the Lovat's Scouts Battalion of the Cameron Highlanders. In June 1918, with victory looming on the Macedonia front, the unit was transferred to the 149th Brigade, 50th Division on the Western Front, where it remained until the end of the war. 2/1st, 2/2nd and 2/3rd Scottish Horse Three 2nd Line regiments were formed in August and September 1914 at Dunkeld and Aberdeen. They moved to Kettering, Northamptonshire and formed 2/1st Scottish Horse Mounted Brigade. At the end of 1915, they moved to Alford, Lincolnshire. On 31 March 1916, the remaining Mounted Brigades were numbered in a single sequence. As a consequence, the 2/1st Scottish Horse Mounted Brigade was redesignated as 19th Mounted Brigade, in Northern Command. In July 1916, the regiments were converted to cyclists (and the brigade became 12th Cyclist Brigade, later 8th