The regiment was formed in 1999 by the amalgamation of the 3rd Battalion The Prince of Wales's Own Regiment of Yorkshire (Yorkshire Volunteers); 3rd Battalion The Duke of Wellington's Regiment (Yorkshire Volunteers); and the King's Own Yorkshire Yeomanry (Light Infantry) due to the reforms implemented in consequence of the Strategic Defence Review.

During the summer of 2004 the regiment adopted a single Tactical Recognition Flash (TRF) of the White Rose of Yorkshire on a black background (this design was previously used by the 49th (West Riding) Infantry Division between the First and early in the Second World War).

[3] In November 2004, the regiment dispatched a composite company (Normandy Company) to Basra, Iraq as part of 4th Mechanized Brigade of the Multi-National Division (South East) for a 6-month tour-of-duty.

After this re-structuring, the regiment's structure was as follows:[2] Minden Company was broken up, with the Company HQ forming 299 Parachute Engineer Squadron, and the Doncaster Platoon formed C (Rifles) Company, 5th Battalion, Royal Regiment of Fusiliers.

[2] As part of the Future Infantry Structure (FIS) restructuring of the army announced in 2004, the regiment became the 4th Battalion of the newly created Yorkshire Regiment (14th/15th, 19th and 33rd/76th Foot) on 6 June 2006.