War in Britain, 208–211 A. D. Like Hadrian, Severus paid great attention to strengthening the frontier defences of the empire, particularly the fortifications which linked the Rhine and the Danube. In 208 A. D. when Britain was invaded by the Caledonians, he took the field, accompanied by his two sons. He reinforced Hadrian’s earthen wall between the Tyne and the Solway by a wall of stone, and carried on guerilla warfare against the tribes of the northern part of the island. However, they had not been completely pacified when he died at York in February, 211 A. D., leaving the principate to his sons, Caracalla and Geta, both of whom had previously received the title of Augustus.
Caracalla, 211–217 A. D. The bitter enmity which had long existed between the two brothers continued during a year of joint rule, and divided the empire into rival factions. Then Caracalla, who had previously sought to make himself sole ruler, succeeded in having Geta assassinated. Many of the latter’s friends, among them the prefect Papinian, were executed. Caracalla was cruel and vicious, and displayed no capacity for governing. He relied solely upon the goodwill of the soldiery and courted their support by increased pay and lavish donatives. In 212 A. D., by the famous Antonian Constitution (constitutio Antoniniana) he extended Roman citizenship to all the provincials of the empire, except those who were in a condition of vassalage, such as some of the barbarian peoples who had been settled on waste lands within the Roman borders, and not citizens of organized municipalities (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 uniform[pg 256]ity 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, 218–222 A. D. Thereupon Elagabalus was universally recognized as princeps and entered Rome in the following year. There he introduced the worship of the sun as the supreme deity of the Roman world, and added to the imperial title that of “most exalted priest of the Unconquered Sun God Elagabalus.” His rule was a riot of debauch, in which his associates were worthless favorites, whom he appointed to the highest offices. His grandmother, Julia Maesa, really conducted the government and, realizing his unfitness [pg 257]to rule, forced him to adopt his cousin Severus Alexander with the title of Caesar in 221 A. D. When Elagabalus sought to rid himself of his relative the praetorians forced him to make Alexander his colleague, and finally murdered him (March, 222 A. D.).
Severus Alexander, 222–235 A. D. Marcus Aurelius Severus Alexander was now sole ruler. However, since he was a mere youth, his mother, Julia Mamaea, daughter of Julia Maesa, exercised the powers of a regent. As he grew up Alexander showed himself well-meaning and conscientious, but lacking in self-reliance, and he never emancipated himself from his mother’s tutelage. During his rule the Senate enjoyed a temporary revival of influence. Two councils of senators, one of sixteen and one of seventy members, acted as an imperial cabinet and an advisory legislative council, respectively. At this time, too, the praetorian prefecture became a senatorial office in that it conferred senatorial rank upon its holder. An attempt was made to remedy public abuses, in particular to restore discipline among the troops, and to reduce the military expenditure. But the army had gotten out of hand, especially the praetorians, from whose anger Alexander was unable to protect the noted jurist Paul, who held the praetorian prefecture.
The new Persian empire. The widespread military insubordination was all the more dangerous since new and more aggressive foes began to threaten the integrity of the empire. In 227 A. D. the Parthian dynasty of the Arsacids was overthrown by the Persian Ardaschir (Artaxerxes) who founded the dynasty of the Sassanids. The establishment of this new Persian kingdom was accompanied by a revival of the national Persian religion, Zoroastrianism, and of the Persian claims to the eastern Roman provinces. In 231 the Persians drove the Roman troops out of Mesopotamia and penetrated Cappadocia and Syria. Alexander himself then went to the East, where he took the offensive in the following year. The details of his campaign are uncertain, but at any rate Mesopotamia was recovered and Alexander celebrated a triumph over the Persians in Rome (233 A. D.).
The Germanic campaign and death of Severus Alexander. But the northern frontier was threatened by the attacks of Germanic tribes, and in 234 Alexander assumed the conduct of operations on the Rhine, with his headquarters at Mainz. The barbarians were induced to make peace, but only by the payment of subsidies, and this cost Alexander the respect of the army, who were disgruntled [pg 258]at his policy of retrenchment and his subservience to his mother. A mutiny broke out, led by Gaius Julius Verus Maximinus, a Thracian of peasant origin who had risen from the ranks to high command. Alexander and Julia Mamaea were put to death, and Maximinus was proclaimed Augustus (March, 235 A. D.). With his accession began a half century of confusion and anarchy.