dediticii_). This act was the logical
culmination of the policy of his predecessors who had granted citizenship
to many provincial municipalities and had sanctioned its automatic
extension to soldiers of the legions and auxiliary corps. Perhaps
Caracalla's chief motive was to supply a fresh source of income for the
treasury, which was sadly depleted by his extravagances, for he greatly
increased the number of those liable to the five per cent inheritance tax
which fell only upon Roman citizens. A second motive may well have been
the desire to secure a uniformity of legal status and of municipal
organization throughout the empire.

*Germanic and Parthian wars.* In 213 A. D. an attack of a confederacy of
German tribes, the Alamanni, upon the Raetian frontier was successfully
repelled, and in the next year Caracalla set out for the East, where he
planned to conduct a Parthian war in imitation of the conquests of his
idol, Alexander the Great. In 215, the Parthian king, Vologases V, came to
terms, but when he was dethroned by his brother, Artabanos V, who refused
Caracalla's request for the hand of his daughter, Caracalla prepared to
invade Parthian territory. But before he embarked on his venture he was
assassinated by the order of the praetorian prefect Marcus Opellius
Macrinus, April, 217 A. D.

*Macrinus, 217-218 A. D.* Macrinus was recognized without opposition as
Caracalla's successor, and bestowed upon his young son Diadumenianus the
title of Caesar. He was the first princeps who had not attained senatorial
rank. As a ruler he displayed moderation and good sense, but was lacking
in force. He purchased peace from the Parthians, abolished oppressive
taxes, and sought to lessen the military burden by cancelling the
increases of pay which Caracalla had granted to the troops. This latter
step cost him the support of the soldiery, and part of the Syrian army
declared its allegiance to the fourteen-year-old Bassianus, a great-nephew
of Julia Domna, the Syrian wife of Septimius Severus. Bassianus could
claim to be a representative of the house of Severus, and consequently was
hailed as Imperator under the name of Marcus Aurelius Antoninus. However,
he is better known as Elagabalus, for he was by hereditary right the
priest of the Sun God worshipped under that name at Emesa.

Macrinus tried to suppress the revolt, but he was defeated near Antioch,
and he and his son were captured and killed (June, 218 A. D.).

*Elagabalus,