The Derbyshire Yeomanry was a yeomanry regiment of the British Army, first raised in 1794, which served as a cavalry regiment and dismounted infantry regiment in the First World War and provided two reconnaissance regiments in the Second World War, before being amalgamated with the Leicestershire Yeomanry to form the Leicestershire and Derbyshire Yeomanry in 1957.

The Leicestershire Yeomanry (Prince Albert's Own) was a yeomanry regiment of the British Army, first raised in 1794 and again in 1803, which provided cavalry and mounted infantry in the Second Boer War and the First World War and provided two field artillery regiments of the Royal Artillery in the Second World War, before being amalgamated with the Derbyshire Yeomanry to form the Leicestershire and Derbyshire (Prince Albert's Own) Yeomanry in 1957. The regiment's lineage is currently perpetuated by E (Leicestershire and Derbyshire Yeomanry) Squadron of the Royal Yeomanry.