[1] The Yeomanry was not intended to serve overseas, but due to the string of defeats during Black Week in December 1899, the British government realized they were going to need more troops than just the regular army.

A Royal Warrant was issued on 24 December 1899 to allow volunteer forces to serve in the Second Boer War.

In 1908, it was transferred into the Territorial Force, returning to a cavalry role and equipped as hussars, under the new title of The Warwickshire Yeomanry.

Volunteers of the regiment saved 763 horses, receiving a Military Cross and twelve Meritorious Service Medals.

It was withdrawn in April 1918, and amalgamated with the 1/1st South Nottinghamshire Hussars into B Battalion, Machine Gun Corps, soon renamed the 100th (Warwickshire and South Nottinghamshire Yeomanry) Battalion, Machine Gun Corps,[8] which would serve on the Western Front for the remainder of the war.

[9] On 27 May 1918 this unit was on board the transport vessel SS Leasowe Castle which was sunk by SM UB-51 with a loss of 101 lives.

[18] The regiment did not mechanise before the outbreak of the Second World War; on mobilisation, it was attached to the 1st Cavalry Division, and moved in 1940 to the Middle East, where it saw service in Iraq and Syria in 1941.

[19] The regiment then saw service in the North African Campaign, fighting at the Second Battle of El Alamein whilst attached to the 2nd New Zealand Division.

[20] On 1 January 1947, the TA was reconstituted, and the regiment followed suite, reforming as the Warwickshire Yeomanry and was armed with tanks shortly afterwards.

[21][22] It was then placed directly under Northern Command and was reorganised into three squadrons:[21][22] After formation, the regiment gained its affiliation with the 13th/18th Royal Hussars.

[23] In 1956, the British Government announced its intention to reduce the size of the Territorial Army, due to its high running costs.