Grey Momus was strongly-built, heavy-shouldered grey horse, bred at Sledmere Stud in Yorkshire by Sir Tatton Sykes, 4th Baronet. He was sired by Comus, who finished third in the 1812 Epsom Derby before becoming a successful sire of winners. His dam, an unnamed mare by Cervantes, also produced a mare who became the ancestor of the Thoroughbred family known as 2-e, which produced such horses as Reigh Count, Candy Spots and Granville.
