The 1st Mounted Division was a
YeomanryDivision of the
British Army active during
World War I. It was formed in August 1914 for the home defence of the United Kingdom from four existing mounted brigades of the
Territorial Force, each of three regiments of
Yeomanry.[1] The divisional order of battle changed often, as the 1st Line[a] brigades left for service overseas and were replaced by 2nd Line formations. It was converted to the 1st Cyclist Division in July 1916, and was broken up in November 1916 without being involved in active service.[1] It remained in
East Anglia throughout its existence.
An unrelated 1st Mounted Division was formed in July 1916, from the
3rd Mounted Division, lasting until September 1917. Another incarnation of 1st Mounted Division was created in April 1918 from the
Yeomanry Mounted Division, lasting until July 1918.
Later in the month, a decision was made to concentrate mounted troops in the
Churn area of
Berkshire and at the end of August 1914 these were formed into a new
2nd Mounted Division. The original division was designated as 1st Mounted Division and gained three more 1st Line[a] mounted brigades –
South Wales,
Welsh Border, and
North Midland – to replace the 1st South Midland, 2nd South Midland, and Notts. and Derby brigades.[5]
As the 1st Line mounted brigades left for overseas service, they were replaced by 2nd Line formations. As with other 2nd Line divisions – which the 1st Mounted Division was in all but name – the division experienced considerable problems with regard to equipment and personnel. Even as late as July 1915, some
Royal Horse Artillery batteries were without guns, wagons or harnesses, machine guns were lacking and few of the men had fired a recruits' course of musketry.[5]
By the beginning of March 1916, the last 1st Line brigades had left and the division was now composed entirely of 2nd Line formations.[5] On 31 March 1916, the remaining mounted brigades were ordered to be numbered in a single sequence and the division now commanded the
1st,
2nd,
3rd and
4th Mounted Brigades.[4]
A further reorganization in November 1916 saw the 1st Cyclist Division broken up. The cyclist brigades were dispersed and the yeomanry regiments were amalgamated in pairs to form Yeomanry Cyclist Regiments in new cyclist brigades.[5]
When the original division was converted to a cyclist division in July 1916, the
3rd Mounted Division was renumbered as the 1st Mounted Division as it was the only remaining mounted division.[b] It, too, was converted to cyclists as
The Cyclist Division on 4 September 1917.[11]
^2nd South Midland Mounted Brigade left for the 2nd Mounted Division in September 1914. It was replaced by the
Welsh Border Mounted Brigade.[21]
^Nottinghamshire and Derbyshire Mounted Brigade left for the 2nd Mounted Division in September 1914. It was replaced by the
North Midland Mounted Brigade.[21]
1st Mounted Division – September 1914 to September 1915
The 1st Mounted Division had the following structure after the departure of three of the original brigades to the
2nd Mounted Division and before the 1st Line mounted brigades started to be replaced by 2nd Line formations:[15]
1st Mounted Division – September 1915 to March 1916
The 1st Mounted Division had the following structure after the departure of the last 1st Line mounted brigade and before the mounted brigades were numbered:[15]
^2/1st Welsh Horse Yeomanry joined the 2/1st South Wales Mounted Brigade in July 1915 as a fourth regiment. By May 1916, the regiment had been absorbed into the 2/1st Montgomeryshire Yeomanry.[19]
^
abIn 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 into 1st Line (liable for overseas service) and 2nd Line (home service for those unable or unwilling to serve overseas) units.[2] 2nd Line units performed the home defence role, although most of these were also posted abroad in due course.[3] Likewise, existing pre-war formations (
brigades and
divisions) formed duplicate 2nd Lines with the same structure as their 1st Line parents.[4]
^British divisions were converted to the
British Indian Army standard whereby brigades only retained one British regiment or battalion and most support units were Indian (artillery excepted).
^
abBecke[7] does not show the cyclist battalions as being attached to the division in May or July 1916, but shows them assigned to the cyclist brigades in September 1916. It is reasonable to assume that they remained attached to the division in the interim.
Becke, Major A.F. (1936). Order of Battle of Divisions Part 2A. The Territorial Force Mounted Divisions and the 1st-Line Territorial Force Divisions (42–56). London:
His Majesty's Stationery Office.
ISBN1-871167-12-4.