Incitatus Dio (155-235 AD) indicated that the horse was attended to by servants and was fed oats mixed with gold flake, and that Caligula made the horse a priest. The accuracy of the received history is generally questioned. Historians such as Anthony A. Barrett suggest that later Roman chroniclers such as Suetonius and Dio Cassius were influenced by the political situation of their own times, when it may have been useful to the current emperors to discredit the earlier Julio-Claudian emperors. Also, the lurid nature of the story added spice to their narratives, winning them additional readers. One suggestion is that
Coronation of the Holy Roman Emperor and Constantia we see the Roman imperial ritual in substantially its final form; the imperial coronation ritual used for Henry VII in 1312 and that found in the Roman Pontifical of 1520 differ from it only in certain details. The Emperor and Empress go in procession to St. Mary in Turri, the choir singing, "Behold, I send an angel" (1312--The Emperor is received as a brother canon by the canons of the church and dressed in a surplice and an almuce.) The Emperor takes the Oath to defend the Roman Church and swears fealty to the Pope and his successors