A helmet in my collection. The 3rd (Prince of Wales's) Dragoon Guards was a cavalry regiment in the British Army, first raised in 1685. It saw service for three centuries, before being amalgamated into the 3rd / 6th Dragoon Guards in 1922. The regiment was first raised as the Earl of Plymouth's Regiment of Horse in 1685, by the regimenting of various independent troops, and ranked as the 4th Regiment of Horse. In 1746 it was ranked as the 3rd Dragoon Guards, and formally titled in 1751 as the 3rd Regiment of Dragoon Guards. Shortly thereafter, in 1765, it took the title 3rd (Prince of Wales's) Dragoon Guards, for the future George IV. After service in the First World War, it retitled as 3rd Dragoon Guards (Prince of Wales's) in 1921, and was amalgamated with the 6th Dragoon Guards (Carabiniers) to form the 3rd/6th Dragoon Guards the following year.