In 1782 The Fifth Regiment of Foot became His Majesty’s Fifth (Northumberland) Regiment of Foot.
Whilst in the Peninsula War the regiment earned the nicknames, “The Old and Bold," "The Fighting Fifth," also "Lord Wellington's Bodyguard." It formed part of a small force which beat off an overwhelming body of the enemy at El Boden in 1811, a performance which Wellington notified to the Army as a memorable example of what can be done by steadiness, discipline, and confidence." The Regiment was in the 3rd Division, 2nd Brigade under command of Major General Charles Colville.