The POA was developed in the United States in the 1950s by Les Boomhower, a Shetland pony breeder in Iowa. The foundation stallion of the breed was an Arabian/Appaloosa/Shetland pony cross with Appaloosa markings named Black Hand. Boomhower appreciated the stallion's conformation and disposition and decided to use him to develop a new breed of Appaloosa-colored ponies. In 1954, Boomhower and a group of associations founded the Pony of the Americas Club, with Black Hand receiving the first registration number. A year later, twelve ponies and twenty-three members had been registered. The club's goal was to develop a medium-sized pony for older children and small adults, with the coloration of the Appaloosa, the refinement of the Arabian and the muscle and bone of an American Quarter Horse. Originally the height requirement called for ponies between ; in 1963 this was changed to a range of , and in 1985 a final change was made to height, raising the upper limit to .