He won two World Grand Championships and was trained, owned and ridden by Colonel J. L. Haynes.
Haynes Peacock was by Wilson's Allen, an early Tennessee Walking Horse sire, and out of a Standardbred mare.
[1] In 1939, Old Dan was exhibited at a small show in Tennessee and was seen by Colonel J. L. Haynes.
Haynes soon bought the horse and at the age of twelve years, had him registered with the Tennessee Walking Horse Breeders' and Exhibitors' Association as Haynes Peacock.
Haynes Peacock, ridden by Haynes, won World Grand Championships at the Tennessee Walking Horse National Celebration in the years 1940 and 1941, making him the first repeat champion.