The 16th/5th The Queen's Royal Lancers was a cavalry regiment of the British Army. It was formed by the amalgamation of the 16th The Queen's Lancers and the 5th Royal Irish Lancers in 1922. The reason for the uniquely atypical regimental title was that the 5th had been re-raised in 1858 almost 60 years after being disbanded, and when re-raised took precedence after the 17th Lancers. After service in the Second World War and the Gulf War, the regiment amalgamated with the 17th/21st Lancers to form the Queen's Royal Lancers in 1993.

There are 13 cavalry Regiments of the British Army each with its own unique cap badge, regimental traditions, and history. Of the currently nine regular cavalry regiments, two serve as armoured regiments, three as armoured cavalry regiments, three as light cavalry, and one as a mounted ceremonial regiment. There are also four yeomanry regiments of the Army Reserve, of these, three serve as light cavalry and one as an armoured regiment. Each yeomanry light cavalry unit has been paired with a regular unit of the same role, the armoured yeomanry unit is paired with the two regular armoured units. All except the Household Cavalry are part of the British Army's Royal Armoured Corps.