The disappearance of the great lyric and poetic styles, the fossilizing of education as it came to be completely based on rhetoric (paideia), and the growing importance of philosophical and religious polemical literature among both pagans and Christians were the basic traits that, as early as the 3rd century, foreshadowed the intellectual life of the late empire. Military anarchy and the disintegration of the empire (235–270) Succession of emperors and usurpers
The period from the death of Severus Alexander to the time of Claudius II Gothicus was marked by usurpations and barbarian invasions. After Maximinus the Thracian, who bravely fought the Alemanni but showed great hostility toward the Senate and the educated elite, the Gordians rose to power as a result of a revolt by wealthy African landowners. A senatorial reaction first imposed civilian emperors, Pupienus and Balbinus together, and then named Gordian III, a youth backed by his father-in-law, the praetorian prefect Timesitheus. Gordian III was murdered by the soldiers during a campaign against the Persians and was replaced, first by Philip the Arabian and then by Decius, both soldiers. Decius tried to restore Roman traditions and also persecuted the Christians, but he was killed by the Goths in 251 in a battle near the Black Sea. From 253 to 268 two Roman senators, Valerian and his son Gallienus, reigned. Valerian revived the persecution of the Christians, but he was captured by the Persians during a disastrous campaign and died in captivity (260; see photograph). His son then reigned alone, facing multiple invasions and several usurpations. He moved constantly between the Rhine and the Danube, achieving brilliant victories (Milan in 262, the Nestus in 267), but the Pannonian army raised several competitors against him (Ingenuus, Regalianus, Aureolus). Too busy to protect the Gauls against the Franks and the Alemanni and the East against the Persians, he had to tolerate the formation of the Gallic empire under the praetorian prefect Marcus Cassianius Postumus (259–268) and the Palmyrene kingdom of Odenathus (260–267). Some of his reforms were a foreshadowing of the future: the senators were practically excluded from the army; the equites received the majority of commands and of provincial governorships; and the composition of the army was modified by the creation of new army corps and especially of a strong cavalry, which was placed under the command of a single leader and charged with closing the breaches that the barbarians were opening along the frontiers. Upon his father’s death Gallienus had put an end to the persecution of the Christians, preferring to fight the new religion through intellectual means; to that end, he favoured the ancient Greek cults (Demeter of Eleusis) and protected the Neoplatonist philosopher Plotinus. These initiatives increased the number of his enemies, particularly among the patriotic senators and the Pannonian generals. While Gallienus was in Milan besieging the usurper Aureolus, he was killed by his chiefs of staff, who proclaimed Claudius II (268), the first of the Illyrian emperors. The new emperor won a great victory against the Alemanni on the Garda lake and overwhelmed the Goths in Naissus (269) but died of the plague in 270. This fatal period brought to light one of the major defects of the empire: the lack of a legitimate principle of succession and the preponderant role of the army in politics. The structures that had created the strength of the principate were weakened, and the empire required deep reforms. Gallienus had felt their necessity but had been too weak to impose them.
The surrender of the emperor Valerian to the Persian king Shāpūr, rock relief, ad 260, in the province of Fārs, Iran.© lukakikina/Fotolia
The barbarian invasions
The Goths were Germans coming from what is now Sweden and were followed by the Vandals, the Burgundians, and the Gepidae. The aftereffect of their march to the southeast, toward the Black Sea, was to push the Marcomanni, the Quadi, and the Sarmatians onto the Roman limes in Marcus Aurelius’ time. Their presence was brusquely revealed when they attacked the Greek towns on the Black Sea about 238. Timesitheus fought against them under Gordian III, and under Philip and Decius they besieged the towns of Moesia and Thrace, led by their kings, Ostrogotha and Kniva. Beginning in 253, the Crimean Goths and the Heruli appeared and dared to venture on the seas, ravaging the shores of the Black Sea and the Aegean as well as several Greek towns. In 267 Athens was taken and plundered despite a strong defense by the historian Dexippus. After the victories of Gallienus on the Nestus and Claudius at Naissus (Nish), there was for a time less danger. But the countries of the middle Danube were still under pressure by the Marcomanni, Quadi, Iazyges, Sarmatians, and the Carpi of free Dacia, who were later joined by the Roxolani and the Vandals. In spite of stubborn resistance, Dacia was gradually overwhelmed, and it was abandoned by the Roman troops, though not evacuated officially. When Valerian was captured in ad 259/260, the Pannonians were gravely threatened, and Regalianus, one of the usurpers proclaimed by the Pannonian legions, died fighting the invaders. The defense was concentrated around Sirmium and Siscia-Poetovio, the ancient fortresses that had been restored by Gallienus, and many cities were burned.
In the West the invasions were particularly violent. The Germans and the Gauls were driven back several times by the confederated Frankish tribes of the North Sea coast and by the Alemanni from the middle and upper Rhine. Gallienus fought bitterly, concentrating his defense around Mainz and Cologne, but the usurpations in Pannonia prevented him from obtaining any lasting results. In 259–260 the Alemanni came through the Agri Decumates (the territory around the Black Forest), which was now lost to the Romans. Some of the Alemanni headed for Italy across the Alpine passes; others attacked Gaul, devastating the entire eastern part of the country. Passing through the Rhône Valley, they eventually reached the Mediterranean; and some bands even continued into Spain. There they joined the Franks, many of whom had come by ship from the North Sea, after having plundered the western part of Gaul. Sailing up the estuaries of the great rivers, they had reached Spain and then, crossing the Strait of Gibraltar, had proceeded to Mauretania Tingitana. Gallienus, outflanked, entrusted Gaul and his young son Saloninus to Postumus, who then killed Saloninus and proclaimed himself emperor. The several invasions had so frightened the people that the new emperor was readily accepted, even in Spain and Britain. He devoted himself first to the defense of the country and was finally considered a legitimate emperor, having established himself as a rival to Gallienus, who had tried in vain to eliminate him but finally had to tolerate him. Postumus governed with moderation, and, in good Roman fashion, minted excellent coins. He, too, was killed by his soldiers, but he had successors who lasted until 274. Difficulties in the East
In the East the frontiers had been fixed by Hadrian at the Euphrates. But under Nero, the Romans had claimed control over the kings of Armenia, and under Caracalla they had annexed Osroëne and Upper Mesopotamia. The Parthian empire had been weak and often troubled, but the Sāsānids were more dangerous. In 241, Shāpūr I (Sapor), an ambitious organizer and statesman, mounted the throne: he united his empire by bringing the Iranian lords into line and by protecting the Zoroastrian religion. He also tolerated the Manichaeans and put an end to the persecutions of the Christians and Jews, thereby gaining the sympathy of these communities. In 252, with a large army at his command, Shāpūr imposed Artavasdes on Armenia, attacked Mesopotamia, and took Nisibis. In 256 his advance troops entered Cappadocia and Syria and plundered Antioch, while Doura-Europus, on the middle Euphrates, was likewise falling to him. Valerian had rushed to its aid, but he could not remedy the situation; and in 259 or 260 he was imprisoned by Shāpūr during operations about which little is known. Mesopotamia was lost and Rome was pushed back to the Euphrates. Cappadocia, Cilicia, and Syria were again plundered, and a puppet emperor was appointed in Antioch. But these victories were transitory: in Osroëne, Edessa had shown resistance, a defense was organized in Cappadocia and Cilicia, and Odenathus, the prince of Palmyra, took Shāpūr by surprise and forced him back to Iran. Having thus aided the Roman cause, Odenathus then began to act in his own interest: he continued the fight against the Persians and took the title “King of Kings.” The Romans officially entrusted him with the defense of the East and conferred on him the governorship of several provinces; the “kingdom” of Palmyra thus extended from Cilicia to Arabia. He was murdered in 267 without ever having severed his ties with Gallienus. His widow Zenobia had her husband’s titles granted to their son Vaballathus. Then in 270, taking advantage of the deaths of Gallienus and Claudius II, she invaded Egypt and a part of Anatolia. This invasion was followed by a rupture with Rome, and in 271 Vaballathus was proclaimed Imperator Caesar Augustus. The latent separatism of the Eastern provinces and, undoubtedly, some commercial advantages caused them to accept Palmyrene domination without difficulty, as they had, in the past, supported Avidius Cassius and Pescennius Niger against the legitimate emperors. In 272 unity was restored by Aurelian, but Mesopotamia was lost, and the Euphrates became the new frontier of the empire. Economic and social crisis