The Fairfax Morocco Barb stands at stud at Helmsley, Yorkshire. Thomas Fairfax, 3rd Baron Cameron, is granted the Helmsley estate, which had previously been owned by George Villers, 1st Duke of Buckingham and favourite of James I, by Oliver Cromwell for Fairfax's service as a parliamentary general and as "a salve for a bad wound" he suffered when besieging Helmsley Castle in 1644 in the English Civil War. There is a strong possibility that the Fairfax Morocco Barb is one of the four stallions presented in 1637 to Charles I by the Emperor of Morocco.
AKA (Helmsley's) Old Morocco
"About 1653 Fairfax bred Old Bald Peg to the Old Morocco Barb. The outcome was the Old Morocco Mare. It is this General Stud Book connection which establishes the pre-Christian Irish Hobby as a prime source of Thoroughbred sprinting speed."(Speed and the Thoroughbred" by Alexander MacKay-Smith  (page 3).