hat
Herodian has given with most truth the general outline of the expedition
of Caracallus, though, with that love of effect which characterizes him,
he may have unduly embellished the narrative.

The advance of Caracallus was, if Spartianus is to be believed, through
Babylonia. The return may have been (as Dio seems to indicate that it
was) by the way of the Tigris, through Adiabene and Upper Mesopotamia.
It was doubtless on the return that Caracallus committed a second and
wholly wanton outrage upon the feelings of his adversary, by violating
the sanctity of the Parthian royal sepulchres, and dispersing their
contents to the four winds. These tombs were situated at Arbela, in
Adiabene, a place which seems to have been always regarded as in some
sort a City of the Dead. The useless insult and impiety were worthy of
one who, like Caracallus, was "equally devoid of judgment and humanity,"
and who has been pronounced by the most unimpassioned of historians
to have been "the common enemy of mankind." A severe reckoning was
afterwards exacted for the indignity, which was felt by the Parthians
with all the keenness wherewith Orientals are wont to regard any
infringement of the sanctity of the grave.

Caracallus appears to have passed the winter at Edessa, amusing himself
with hunting and charioteering after the fatigues of his campaign. In
the spring he threatened another advance into Parthian territory, and
threw the Medes and Parthians into great alarm. He had not, however, the
opportunity of renewing his attack. On April 8, A.D. 217, having quitted
Edessa with a small retinue for the purpose of visiting a famous temple
of the Moon-God near Carrhaa, he was surprised and murdered on the way
by Julius Martialis, one of his guards. His successor, Macrinus, though
a Praetorian prefect, was no soldier, and would willingly have retired
at once from the war. But the passions of the Parthians had been roused.
Artahanus possessed the energy and spirit which most of the recent
monarchs had lacked; and though defeated when taken at disadvantage, and
unable for some months to obtain any revenge, had employed the winter
in the collection of a vast army, and was determined to exact a heavy
retribution for the treacherous massacre of Ctesiphon and the wanton
impiety of Arbela. He had already taken the field and conducted his
troops to the neighborhood of the Roman frontier when Caracallus lost
his life. Macrinus was scarcely acknowledge