The Imperial Yeomanry were formed as a direct result of the need for large numbers of horse-borne troops to counter a fast-moving and wily enemy over the enormous distances of the South African veldt.
It quickly became apparent that an immediate re-think on tactics was necessary following the disastrous 'Black Week' of December 1899 when the British Army suffered three humiliating defeats in just six days at the hands of the Boers. The Boers - being predominantly horsemen - had to be countered with mounted infantry, as the British simply had not enough cavalry to meet the threat.
At the war's beginning there had been many offers to provide men and horses for service in South Africa by enthusiastic Colonels of county yeomanry regiments, eager to join the fray. All such offers were rejected by the War Department, no doubt thinking that the Regular Army were more than adequate for the job without having to resort to part-time cavalry from the yeomanry.
The Imperial Yeomanry was authorised to be formed by Royal Warrant on Christmas Eve 1899. County yeomanry regiments were asked to provide volunteer companies in the same way that infantry battalions of the Volunteer Force provided companies for overseas service to augment the regulars.
The yeomanry troopers from the county regiments who had volunteered for overseas service in the IY were in turn augmented by civilian volunteers recruited directly in to the IY for South African service.
- Her Majesty's Government have decided to raise for active service in South Africa a mounted infantry force, to be named "The Imperial Yeomanry".
- The force will be recruited from the Yeomanry, but Volunteers and civilians who possess the requisite qualifications will be specially enlisted in the Yeomanry for this purpose.
- The force will be organized in companies of 115 rank and file, 1 one captain and four subalterns to each company, preferably Yeomanry officers.
- The term of enlistment for officers and men will be for one year, or not less than the period of the war.
- Officers and men will bring their own horses, clothing, saddlery and accoutrements. Arms, ammunition, camp equipment and transport will be provided by the government.
- The men to be dressed in Norfolk jackets, of woollen material of neutral colour, breeches and gaiters, lace boots, and felt hats. Strict uniformity of pattern will not be insisted on.
- Pay to be at Cavalry rates, with a capitation grant for horses, clothing, etc.
- Applications for enrolment should be addressed to colonels commanding Yeomanry regiments, or to general officers commanding districts, to whom instructions will be issued.
- Qualifications are: Candidates to be from 20 to 35 years of age, and of good character. Volunteers or civilian candidates must satisfy the Colonel of the regiment through which they enlist that they are good riders and marksmen, according to the Yeomanry standard.
Thirty-nine battalions were eventually formed and the IY remained in South Africa as late as 1903 to help in the stabilisation process.
In the UK, all county yeomanry regiments were reorganised in 1901 in to a collective force under the IY umbrella (though they retained their individual unit identities) before becoming absorbed (along with the Volunteer Force) in to the Territorial Force in 1908 as a consequence of the Haldane reforms.
The IY was moderately successful and valuable lessons were learned. It proved that volunteers could serve alongside regulars and prompted a re-think in how part-time volunteers could augment the regular units in wartime - something that proved vitally important prior to the Great War.