The adoption of the horse for chariots, wagons and riding had a major impact on human societies, but it has proved difficult to reliably identify early domesticated horses in the archaeological record. This comparative study of equine palaeopathology addresses the problem by analysing wild and domestic horses used for traction or riding. Osteological changes to the skull appear to be the result of mechanical and physiological stress from the use of horses for transport. The results are applied to archaeological examples from the Deer Stone-Khirigsuur Complex of Bronze Age Mongolia (1300–700 BC) and show that those horses were probably bridled and used for transport.