The Anglo-Arabian horse is a Thoroughbred crossed with an Arabian horse. The cross can be made between a Thoroughbred stallion and Arabian mare, or vice-versa. It can also be a cross between a Thoroughbred and an Anglo-Arab, an Arabian and an Anglo-Arab, or between two Anglo-Arabians. No matter what the cross, the Anglo-Arabian must have at least 12.5% percent Arabian blood to be considered an Anglo-Arabian.