Herodian (late second, first half third century): Greek historian, author of a History of the Roman Empire since the Death of Marcus Aurelius in which he describes the reign of Commodus (180-192), the Year of the Five Emperors (193), the age of the Severan dynasty (211-235), and the Year of the Six Emperors (238).
The translation was made by Edward C. Echols (Herodian of Antioch's History of the Roman Empire, 1961 Berkeley and Los Angeles) and was put online for the first time by Roger Pearse (Tertullian.Org). The version offered on these pages is hyperlinked and contains notes by Jona Lendering.
Murder of Caracalla
[4.13.1] [Early April 217] The prefect, fearing that Materianus might send this information to the emperor a second time, decided to act now rather than wait and suffer the consequences. This is what he did. In Caracalla's bodyguard was a centurion named Martialis, who was always in the emperor's escort. A few days earlier, Caracalla had executed the centurion's brother on an unproved charge. Moreover, the emperor continually insulted the man, calling him cowardly, effeminate, and Macrinus' darling.
[4.13.2] Learning that Martialis was exceedingly grieved by his brother's death and could no longer endure the emperor's insults, Macrinus summoned the centurion (in whom he had confidence because the man had served him before, and had received many favors from him). The prefect persuaded Martialis to be on the watch for a suitable opportunity to carry out a plot against the emperor. Won over by Macrinus' promises, Martialis, since he hated the emperor and was eager to avenge his brother, gladly promised to do the deed when the proper occasion arose.
[4.13.3] [8 April 217] Not long after they made this agreement, it happened that Caracalla, who was spending the time at Carrhae in Mesopotamia, conceived a desire to leave the imperial quarters and visit the Temple of the Moon, for Selene is the goddess whom the natives particularly adore. The temple was located some distance from Carrhae, and the journey was a long one.note[The temple is in Harran, so there is no distance to cover at all. The truth is that Caracalla set out from Edessa.] Therefore, to avoid involving the entire army, Caracalla made the trip with a few horsemen, intending to sacrifice to the goddess and then return to the city.
[4.13.4] At the halfway point he stopped to relieve himself; ordering his escort to ride off, he went apart with a single attendant. All the horsemen turned aside and withdrew for some distance, respecting the emperor's modesty.
[4.13.5] But when Martialis, who was looking for just such an opportunity, saw Caracalla alone, he ran toward him as if the emperor had summoned him by a gesture to question him or receive some information. Standing over Caracalla after he had uncovered himself, Martialis stabbed the emperor from behind with a dagger he had concealed in his hand. The blow under the shoulder was fatal, and Caracalla died, unsuspecting and undefended.
[4.13.6] When the emperor fell, Martialis leaped upon his horse and fled. Those favorites of Caracalla, the German cavalry who served as his bodyguard, were closer to the scene than the rest, and hence were the first to realize what had happened. These horsemen set out in pursuit of Martialis and cut him down.
[4.13.7] When the rest of the army learned what had occurred, they hurried to the spot, and Macrinus was the first to arrive; standing over the body, he pretended to wail and lament for the emperor. The whole army was grieved and distressed by the affair; they felt they had lost a fellow soldier, a comrade-in-arms, rather than their emperor. And yet they never suspected that it was a plot of Macrinus; they believed that Martialis had done it because of his personal hatred for the emperor.
[4.13.8] Then the soldiers retired, each to his own tent. After burning the body on a pyre and placing the ashes in an urn, Macrinus sent it for burial to the emperor's mother in Antioch. As a result of these similar disasters which befell her two sons, Julia died, either by her own hand or by the emperor's order. Such was the fate suffered by Caracalla and his mother Julia, who lived in the manner I have described above. Caracalla had served as emperor without his father and brother for eleven years.note[In fact six. Eleven is correct if we take his years as Severus' co-ruler into account.]