The American Quarter Horse Association (AQHA) was formed in 1940 to preserve the foundation type Quarter Horse commonly referred to as Steeldusts, or Bulldogs. These horses exhibited the unique traits of a low center of gravity, exceptionally heavy muscling, powerful hindquarters, a good bone structure and hooves, a quiet and trainable disposition, and a high degree of intelligence and natural cow sense. Those characteristics combined to set apart this horse as a unique individual easily distinguished from other equine breeds. The conformation that enabled the forerunner of today's Quarter Horse to leave the starting line in a colonial match race with such blazing speed was the same conformation that allowed the later Quarter Horse to catch and pen a cow with so little effort, and to stay sound doing it. Their disposition enables Quarter Horses to mentally contend with being expected to perform myriad duties and events. The quiet, intelligent foundation Quarter Horse can quickly fire up to catch a cow, and just as quickly return to a calm, quiet state, to complete a full day of hard work. Despite efforts to modernize the quarter horse, the foundation Quarter Horse's history and bloodlines have proven to create a unique and remarkably versatile horse which still exists today.
             When the quarter horse came into his own he had to work for his living, thus the term "the working horse" was born. His owner depended on this horse for his living, whether it was the cowboy, the rancher, the farmer, the circuit riding preacher or the match race contenders. Over time, these horses built and established a reputation as the true working horses. Much was expected and depended on these early working cow horses, and therefore it was necessary and expedient to breed not only for physical ability but also that quiet, unique disposition and intelligence that has given these horses the label of dependability.
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