Darley Arabian
Bulle Rock (foaled c. 1709), sometimes referred to as Bulle Rocke or "Bullyrock", is thought to be the first Thoroughbred stallion brought to America. He was imported in 1730 at the age of 21. He was a bay son of the Darley Arabian and said to be out of a mare by the Byerley Turk, though his maternal lineage is questioned by some sources.