The 15th/19th Hussars was formed from the amalgamation of the 15th Hussars and 19th Hussars in 1922.

It was mechanised and became a unit of the Royal Armoured Corps.

Due to the poor availability of armoured vehicles and tanks at the start of the Second World War, some units were formed to create Motor Machine Gun Brigades. This unit joined the 3rd MMG Bde on 23 June 1940 and remained with it under reorganised as the 28th Armoured Brigade on 01 December 1940.