But as the Persians and the Germans had taken advantage of the philosopher king, so now they took advantage of the emperor saint. In 230 Ardashir, founder of the Sassanid dynasty in Persia, invaded Mesopotamia and threatened Syria. Alexander sent him a philosophical epistle reproving his violence, and arguing that “everyone ought to rest content with his own domain.” Ardashir judged him a weakling, and replied by demanding all Syria and Asia Minor. Accompanied by his mother, the young emperor took the field, and waged with more courage than subtlety an indecisive campaign. History is obscure as to his victories and defeats; in any case Ardashir withdrew from Mesopotamia, perhaps to meet attacks on his eastern front; and the Roman coins of 233 pictured Alexander crowned by Victory and having the Tigris and Euphrates at his feet. Meanwhile the Alemanni and the Marcomanni, noting that the Rhine and Danube garrisons had been depleted to reinforce the legions in Syria, broke through the Roman limes and ravaged eastern Gaul. After celebrating his Persian triumph, Alexander, again with Mamaea at his side, rejoined his army, and led it to Mainz. On his mother’s advice he negotiated with the enemy, offering them an annual sum to keep the peace. His troops condemned his weakness, and mutinied; they had never forgiven his economy, his discipline, and his subordination of them to the Senate and a woman’s rule. They acclaimed as emperor C. Julius Maximinus, commander of the Pannonian legions. The soldiers of Maximinus forced their way into Alexander’s tent, and slew him, his mother, and his friends (235).
It was no whim of history that made the army supreme in the third century; internal causes had weakened the state and left it exposed on every front. The cessation of expansion after Trajan, and again after Septimius Severus, was the signal for attack; and as Rome had conquered nations by dividing them, so now the barbarians began to conquer her by uniting in simultaneous assaults. The necessity of defense exalted the power of arms and the prestige of soldiery; generals replaced philosophers on the throne, and the last reign of the aristocracy yielded to the revived rule of force. Maximinus was a good soldier and no more, the robust son of a Thracian peasant; history assures us that he was eight feet tall, and had a thumb of such circumference that he could wear his wife’s bracelet on it as a ring. He had no education, scorned it, and envied it. In his three years as emperor he never visited Rome, but preferred the life of his camp on the Danube or the Rhine. To support his campaigns and appease his troops, he laid such taxes upon the well to do that an upper-class revolt soon formed against his rule. Gordianus, the wealthy and learned proconsul of Africa, accepted the nomination of his army as a rival emperor; being eighty years old, he associated his son with him in the lethal office; they failed to withstand the forces sent against them by Maximinus; the son was killed in battle, the father killed himself. Maximinus revenged himself by proscriptions and confiscations that almost destroyed the aristocracy. “Every day,” says Herodian, “one could see the richest men of yesterday turned beggars today.” The Senate, which had been reconstituted and reinvigorated by Severus, fought back valiantly; it declared Maximinus an outlaw, and chose two of its members, Maximus and Balbinus, as emperors. Maximus led an improvised army to meet Maximinus, who came down across the Alps and besieged Aquileia. Maximinus was the better general, and had the superior forces; the fate of the Senate and the propertied classes seemed sealed; but a group of Maximinus’ soldiers, who had suffered from his savage punishments, killed him in his tent. Maximus returned in triumph to Rome, and was assassinated, along with Balbinus, by the Praetorian Guard. The Praetorians made a third Gordian emperor, and the Senate confirmed the choice. We shall not repeat in bloody detail the names and battles and deaths of these emperors of anarchy. In the thirty-five years between Alexander Severus and Aurelian, thirty-seven men were proclaimed emperors. Gordian III was slain by his troops while fighting the Persians (244); his successor, Philip the Arab, was defeated and killed at Verona by Decius (249), an Illyrian of wealth and culture whose devotion to Rome well deserved a name so honorable in ancient story. Between campaigns against the Goths he laid out an ambitious program for the restoration of Roman religion, morals, and character, and gave orders for the destruction of Christianity; then he returned to the Danube, met the Goths, saw his son slain beside him, told his wavering army that the loss of any one individual was of little importance, pressed on against the enemy, and was himself struck down in one of the worst defeats in Roman history (251). He was succeeded by Gallus, who was murdered by his troops (253), and then by Aemilianus, who was murdered by his troops (253). The new emperor, Valerian, already sixty, and facing war at once with the Franks, the Alemanni, the Marcomanni, the Goths, the Scythians, and the Persians, made his son Gallienus ruler of the Western Empire, kept the East for himself, and led an army into Mesopotamia. He was too old for his tasks, and soon succumbed. Gallienus, now thirty-five, was a man of courage, intelligence, and a culture that seemed almost out of place in this century of barbaric war. He reformed the civilian administration in the West, led his armies to victory against one after another of the Empire’s enemies, and yet found time to enjoy and patronize philosophy and literature, and promote a transient revival of classic art. But even his varied genius was overwhelmed by the accumulating evils of the time.
In 254 the Marcomanni raided Pannonia and north Italy. In 255 the Goths invaded Macedonia and Dalmatia, Scythians and Goths invaded Asia Minor, the Persians invaded Syria. In 257 the Goths captured the fleet of the Bosporan kingdom, ravaged the Greek cities on the Black Sea coasts, burned Trapezus and enslaved its people, and raided Pontus. In 258 they took Chalcedon, Nicomedia, Prusa, Apamea, Nicaea; in the same year the Persians conquered Armenia, and Postumus declared himself the independent ruler of Gaul. In 259 the Alemanni broke into Italy, but were defeated by Gallienus at Milan. In 260 Valerian was overwhelmed by the Persians at Edessa, and died in captivity at a time and place unknown. Shapur I and his clouds of cavalry advanced through Syria to Antioch, surprised the population in the midst of its games, sacked the city, killed thousands, and led more thousands into slavery. Tarsus was taken and devastated, Cilicia and Cappadocia were overrun, and Shapur returned to Persia laden with spoils. Within a decade three ignominious tragedies had overtaken Rome: a Roman emperor had for the first time fallen in defeat, another had been captured by the enemy, and the unity of the Empire had been sacrificed to the necessity of meeting simultaneous attacks on many fronts. Under the force of these blows, and the disorderly elevation and assassination of emperors by troops, the imperial prestige collapsed; those psychological forces which time consecrates into habitual and unquestioned authority lost their hold upon Rome’s enemies, even upon her subjects and citizens. Revolts broke out everywhere: in Sicily and Gaul the oppressed peasantry flared up in wild jacqueries; in Pannonia Ingenuus proclaimed himself sovereign of the eastern provinces. In 263 the Goths sailed down the Ionian coast, sacked Ephesus, and burned down the great Temple of Artemis. All the Hellenistic East was in terror.