Herodian, History iv. ii

It is the custom among the Romans to deify those of their Emperors who die with sons to succeed them.* This rite is called apotheosis. The whole city takes on the air of a religious festival mingled with mourning. They bury the body of the departed in the customary manner of mortals, giving it a sumptuous funeral, and they fashion a wax image like the deceased in every respect and let it lie in state on a huge ivory couch spread with coverlets interwoven with gold and raised up high at the entrance to the palace. [. . . ] During the most of the daytime a watch is kept on both sides of the couch: on the left by the entire senate wearing black garments, on the right by all the matrons on whom the rank of their husbands or fathers confers honored status; all the latter appear unadorned by gold or necklaces but, clothed in plain white garb, present the appearance of mourners. This is done for seven days, during which physicians make daily visits; they approach the couch, actually examine the "invalid," and issue daily bulletins that his condition is more serious. When he is reported to have died, the noblest of the equestrian order and chosen youths of the senatorial order raise up the couch and convey it along the Sacred Way and place it in state in the ancient Forum, where the Roman magistrates lay down their offices. On either side are some steps like a staircase, and on the one side stands a chorus of noble and patrician children, on the opposite a chorus of matrons of high reputation, singing both hymns of paeans to the departed, intoned in solemn, mournful measure.

After this they lift up the couch again and bear it out of the city to the so-called Field of Mars. There, at the widest part of the field a square structire had been erected, constructed exclusively of very large-sized logs, in the form of chamber. The whole structure is filled inside with firewood and adorned on the outside with coverlets interwoven with gold, ivory statues, and colorful paintings. Above this is another chamber, similar in shape and decoration, but smaller, with its little gates and doors open. A third and fourth, each smaller than the one below, lead to the last and narrowest. [. . .] They carry the couch up into that second chamber and place therein all the spices and incense that the earth produces, and they gather also any fruits, herbs, or juices thatr produce fragrance, and they bring it up and pour it out in profusion. There is no province, no city, no man of reputation or rank, that does not vie in sending these last gifts in honor of the emperor. When there is a huge mound of spices and the whole space is filled, there is a cavalry procession around this structure, and the entire equestrian order rides in a circle around it, in a regular order and wheeling movement, in the Pyrrhic course and rythem.** Chariots are driven around in the same ordered array, bearing the officians in charge [of the ceremony], who are garbed in the purple-boardered toga and wear masks in the likenesses of all the outstanding Roman generals and emperors.

When this ritual has been completed, he who has succeeded to the throne takes a torch and applies it to the chamber. Then the others apply fire on all sides; with the mass of firewood and incense piled there, all is most readily and easily kindled by the fire. Then from the last and narrowest chamber, as from a battlement, an eagle is released to rise up into the upper air with the fire; the bird is believed by the Romans to carry the soul of the emperor from earth to heaven. And from then on the emperor is worshipped along with the other gods.***

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* This is erroneous, as some Emperors were deified even without being succeeded by a son (natural or adopted).
** The Pyrrhic dance was a war dance of Greek origin.
*** The tradition of consecrating the deceased emperor survived into the early Christian period; although the rites of Constantine and a few of his successors were probably little more than a traditional honor, it could also represent that Christianity had still achieved only a partial success in the early period. Constantine, it must be recalled, also associated himself during his reign with Sol Invictus.