Seventeen Cavalry Reserve Regiments were formed by the British Army on the outbreak of the Great War in August 1914.[1] These were affiliated with one or more active cavalry regiments, their purpose being to train replacement drafts for the active regiments. In 1915, the 3rd Line[a] regiments of the Yeomanry were also affiliated with the Cavalry Reserve and, in September 1916, the Household Cavalry Reserve Regiment was formed in Windsor, supplying replacements to the dismounted Household Battalion. In 1917, the regiments underwent major reorganization, being reduced to ten in number.
Although nominally cavalry, many of the drafts ended up being converted into infantry in order to satisfy the manpower demands of trench warfare.
Despite being training and not combat formations, several were involved in the putting down of the Easter Rising in Dublin in April 1916. A little after noon on Easter Monday, a mixed troop of 9th and 12th Lancers, attached to the 6th Cavalry Reserve Regiment at Marlborough Barracks in Phoenix Park, was dispatched to investigate a "disturbance" at Dublin Castle.[3] As they cantered down Sackville Street, they were fired upon by rebels who had taken up positions in and on the roof of the General Post Office. Three troopers were killed instantly and one was mortally wounded, becoming the first military casualties of the rising. The same evening, 1,600 men of the 3rd Reserve Cavalry Brigade (consisting of the 8th, 9th and 10th Cavalry Reserve Regiments) arrived from their barracks at the Curragh to support the local Dublin garrison.[4]
5th Lancers 9th Lancers 12th Lancers 16th Lancers 17th Lancers 21st Lancers 3/1st Bedfordshire Yeomanry 3/1st Lincolnshire Yeomanry 3/1st City of London Yeomanry 2/1st Surrey Yeomanry 3/1st East Riding Yeomanry
2nd
The Curragh
3rd Hussars 4th Hussars 7th Hussars 8th Hussars 3/1st Queen's Own Dorset Yeomanry 2/1st Lancashire Hussars 3/1st County of London Yeomanry 3/3rd County of London Yeomanry 3/1st South Nottinghamshire Hussars 3/1st Queen's Own Oxfordshire Hussars 3/1st Westmorland and Cumberland Yeomanry
3rd Dragoon Guards 4th Dragoon Guards 6th Dragoon Guards 7th Dragoon Guards 1st Dragoons 2nd Dragoons 3/1st Berkshire Yeomanry 3/1st Hertfordshire Yeomanry 3/1st Duke of Lancaster's Own Yeomanry 3/1st Northamptonshire Yeomanry 3/1st North Somerset Yeomanry 3/1st Queen's Own Yorkshire Dragoons
Notes
^In accordance with the Territorial and Reserve Forces Act 1907 (7 Edw. 7, c.9) which brought the Territorial Force into being, the TF was intended to be a home defence force for service during wartime and members could not be compelled to serve outside the country. However, on the outbreak of war on 4 August 1914, many members volunteered for Imperial Service. Therefore, TF units were split 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.[2]
^Ciaran Byrne, The Harp and Crown, the History of the 5th (Royal Irish) Lancers, 1902 - 1922, p. 105
^General J.G. Maxwell, From the General Officer, Commanding-in-Chief, The Forces in Ireland. To the Field-Marshal, Commanding-in-Chief, The Home Forces. 25 May 1916