For the band, see Diocletian (band).
Diocletian (; Latin: Gaius Aurelius Valerius Diocletianus Augustus), born Diocles (244–312), was a Roman emperor from 284 to 305. Born to a family of low status in Dalmatia, Diocletian rose through the ranks of the military to become Roman cavalry commander to the Emperor Carus. After the deaths of Carus and his son Numerian on campaign in Persia, Diocletian was proclaimed emperor. The title was also claimed by Carus' other surviving son, Carinus, but Diocletian defeated him in the Battle of the Margus. Diocletian's reign stabilized the empire and marks the end of the Crisis of the Third Century. He appointed fellow officer Maximian as Augustus, co-emperor, in 286. Diocletian reigned in the Eastern Empire, and Maximian reigned in the Western Empire.
Diocletian delegated further on 1 March 293, appointing Galerius and Constantius as Caesars, junior co-emperors, under himself and Maximian respectively. Under this 'tetrarchy', or "rule of four", each emperor would rule over a quarter-division of the empire. Diocletian secured the empire's borders and purged it of all threats to his power. He defeated the Sarmatians and Carpi during several campaigns between 285 and 299, the Alamanni in 288, and usurpers in Egypt between 297 and 298. Galerius, aided by Diocletian, campaigned successfully against Sassanid Persia, the empire's traditional enemy. In 299 he sacked their capital, Ctesiphon. Diocletian led the subsequent negotiations and achieved a lasting and favourable peace.
Diocletian separated and enlarged the empire's civil and military services and reorganized the empire's provincial divisions, establishing the largest and most bureaucratic government in the history of the empire. He established new administrative centres in Nicomedia, Mediolanum, Sirmium, and Trier, closer to the empire's frontiers than the traditional capital at Rome. Building on third-century trends towards absolutism, he styled himself an autocrat, elevating himself above the empire's masses with imposing forms of court ceremonies and architecture. Bureaucratic and military growth, constant campaigning, and construction projects increased the state's expenditures and necessitated a comprehensive tax reform. From at least 297 on, imperial taxation was standardized, made more equitable, and levied at generally higher rates.
Not all of Diocletian's plans were successful: the Edict on Maximum Prices (301), his attempt to curb inflation via price controls, was counterproductive and quickly ignored. Although effective while he ruled, Diocletian's tetrarchic system collapsed after his abdication under the competing dynastic claims of Maxentius and Constantine, sons of Maximian and Constantius respectively. The Diocletianic Persecution (303–11), the empire's last, largest, and bloodiest official persecution of Christianity, failed to eliminate Christianity in the empire; indeed, after 324, Christianity became the empire's preferred religion under its first Christian emperor, Constantine.
In spite of these failures and challenges, Diocletian's reforms fundamentally changed the structure of Roman imperial government and helped stabilize the empire economically and militarily, enabling the empire to remain essentially intact for another 150 years despite being near the brink of collapse in Diocletian's youth. Weakened by illness, Diocletian left the imperial office on 1 May 305, and became the first Roman emperor to abdicate the position voluntarily. He lived out his retirement in his palace on the Dalmatian coast, tending to his vegetable gardens. His palace eventually became the core of the modern-day city of Split in Croatia.
Diocletian was born near Salona in Dalmatia (Solin in modern Croatia), some time around 244. His parents gave him the Greek name Diocles, or possibly Diocles Valerius. The modern historian Timothy Barnes takes his official birthday, 22 December, as his actual birthdate. Other historians are not so certain. Diocles' parents were of low status, and writers critical of him claimed that his father was a scribe or a freedman of the senator Anullinus, or even that Diocles was a freedman himself. The first forty years of his life are mostly obscure. The Byzantine chronicler Joannes Zonaras states that he was DuxMoesiae, a commander of forces on the lower Danube. The often-unreliable Historia Augusta states that he served in Gaul, but this account is not corroborated by other sources and is ignored by modern historians of the period. The first time Diocletian's whereabouts are accurately established, in 282, he was made by the newly Emperor Carus commander of the Protectores domestici, the élite cavalry force directly attached to the Imperial household – a post that earned him the honour of a consulship in 283. As such, he took part in Carus' subsequent Persian campaign.
Death of Numerian
Carus's death, amid a successful war with Persia and in mysterious circumstances – he was believed (perhaps as a result of later Diocletianic propaganda) to have been struck by lightning – left his sons Numerian and Carinus as the new Augusti. Carinus quickly made his way to Rome from his post in Gaul as imperial commissioner and arrived there by January 284, becoming legitimate Emperor in the West. Numerian lingered in the East. The Roman withdrawal from Persia was orderly and unopposed. The Sassanid king Bahram II could not field an army against them as he was still struggling to establish his authority. By March 284, Numerian had only reached Emesa (Homs) in Syria; by November, only Asia Minor. In Emesa he was apparently still alive and in good health: he issued the only extant rescript in his name there,[notes 1] but after he left the city, his staff, including the prefect (Numerian's father-in-law, and as such the dominant influence in the Emperor's entourage)Aper, reported that he suffered from an inflammation of the eyes. He travelled in a closed coach from then on. When the army reached Bithynia, some of the soldiers smelled an odor emanating from the coach. They opened its curtains and inside they found Numerian dead. Both Eutropius and Aurelius Victor describe Numerian's death as an assassination.
Aper officially broke the news in Nicomedia (İzmit) in November. Numerianus' generals and tribunes called a council for the succession, and chose Diocles as Emperor, in spite of Aper's attempts to garner support. On 20 November 284, the army of the east gathered on a hill 5 kilometres (3.1 mi) outside Nicomedia. The army unanimously saluted Diocles as their new augustus, and he accepted the purple imperial vestments. He raised his sword to the light of the sun and swore an oath disclaiming responsibility for Numerian's death. He asserted that Aper had killed Numerian and concealed it. In full view of the army, Diocles drew his sword and killed Aper. According to the Historia Augusta, he quoted from Virgil while doing so. Soon after Aper's death, Diocles changed his name to the more Latinate "Diocletianus", in full Gaius Aurelius Valerius Diocletianus.
Conflict with Carinus
After his accession, Diocletian and Lucius Caesonius Bassus were named as consuls and assumed the fasces in place of Carinus and Numerianus. Bassus was a member of a senatorial family from Campania, a former consul and proconsul of Africa, chosen by Probus for signal distinction. He was skilled in areas of government where Diocletian presumably had no experience. Diocletian's elevation of Bassus as consul symbolized his rejection of Carinus' government in Rome, his refusal to accept second-tier status to any other emperor, and his willingness to continue the long-standing collaboration between the empire's senatorial and military aristocracies. It also tied his success to that of the Senate, whose support he would need in his advance on Rome.
Diocletian was not the only challenger to Carinus' rule: the usurper M. Aurelius Julianus, Carinus' corrector Venetiae, took control of northern Italy and Pannonia after Diocletian's accession. Julianus minted coins from the mint at Siscia (Sisak, Croatia) declaring himself as emperor and promising freedom. It was all good publicity for Diocletian, and it aided in his portrayal of Carinus as a cruel and oppressive tyrant. Julianus' forces were weak, however, and were handily dispersed when Carinus' armies moved from Britain to northern Italy. As leader of the united East, Diocletian was clearly the greater threat. Over the winter of 284–85, Diocletian advanced west across the Balkans. In the spring, some time before the end of May, his armies met Carinus' across the river Margus (Great Morava) in Moesia. In modern accounts, the site has been located between the Mons Aureus (Seone, west of Smederevo) and Viminacium, near modern Belgrade, Serbia.
Despite having the stronger, more powerful army, Carinus held the weaker position. His rule was unpopular, and it was later alleged that he had mistreated the Senate and seduced his officers' wives. It is possible that Flavius Constantius, the governor of Dalmatia and Diocletian's associate in the household guard, had already defected to Diocletian in the early spring. When the Battle of the Margus began, Carinus' prefect Aristobulus also defected. In the course of the battle, Carinus was killed by his own men. Following Diocletian's victory, both the western and the eastern armies acclaimed him augustus. Diocletian exacted an oath of allegiance from the defeated army and departed for Italy.
Diocletian may have become involved in battles against the Quadi and Marcomanni immediately after the Battle of the Margus. He eventually made his way to northern Italy and made an imperial government, but it is not known whether he visited the city of Rome at this time. There is a contemporary issue of coins suggestive of an imperial adventus (arrival) for the city, but some modern historians state that Diocletian avoided the city, and that he did so on principle, as the city and its Senate were no longer politically relevant to the affairs of the empire and needed to be taught as much. Diocletian dated his reign from his elevation by the army, not the date of his ratification by the Senate, following the practice established by Carus, who had declared the Senate's ratification a useless formality. However, Diocletian was to offer proof of his deference towards the Senate by retaining Aristobulus as ordinary consul and colleague for 285 (one of the few instances during the Late Empire in which an emperor admitted a privatus as his colleague) and by creating senior senators Vettius Aqulinus and Junius Maximus ordinary consuls for the following year – for Maximus, it was his second consulship.
Nevertheless, if Diocletian ever did enter Rome shortly after his accession, he did not stay long; he is attested back in the Balkans by 2 November 285, on campaign against the Sarmatians.
Diocletian replaced the prefect of Rome with his consular colleague Bassus. Most officials who had served under Carinus, however, retained their offices under Diocletian. In an act of clementia denoted by the epitomator Aurelius Victor as unusual, Diocletian did not kill or depose Carinus' traitorous praetorian prefect and consul Ti. Claudius Aurelius Aristobulus, but confirmed him in both roles. He later gave him the proconsulate of Africa and the post of urban prefect for 295. The other figures who retained their offices might have also betrayed Carinus.
Maximian made co-emperor
The assassinations of Aurelian and Probus demonstrated that sole rulership was dangerous to the stability of the empire. Conflict boiled in every province, from Gaul to Syria, Egypt to the lower Danube. It was too much for one person to control, and Diocletian needed a lieutenant. At some time in 285 at Mediolanum (Milan),[notes 2] Diocletian raised his fellow-officer Maximian to the office of caesar, making him co-emperor.
The concept of dual rulership was nothing new to the Roman Empire. Augustus, the first Emperor, had nominally shared power with his colleagues, and more formal offices of Co-Emperor had existed from Marcus Aurelius on. Most recently, Emperor Carus and his sons had ruled together, albeit unsuccessfully. Diocletian was in a less comfortable position than most of his predecessors, as he had a daughter, Valeria, but no sons. His co-ruler had to be from outside his family, raising the question of trust. Some historians state that Diocletian adopted Maximian as his filius Augusti, his "Augustan son", upon his appointment to the throne, following the precedent of some previous Emperors. This argument has not been universally accepted.
The relationship between Diocletian and Maximian was quickly couched in religious terms. Around 287 Diocletian assumed the title Iovius, and Maximian assumed the title Herculius. The titles were probably meant to convey certain characteristics of their associated leaders. Diocletian, in Jovian style, would take on the dominating roles of planning and commanding; Maximian, in Herculian mode, would act as Jupiter's heroic subordinate. For all their religious connotations, the emperors were not "gods" in the tradition of the Imperial cult—although they may have been hailed as such in Imperial panegyrics. Instead, they were seen as the gods' representatives, effecting their will on earth. The shift from military acclamation to divine sanctification took the power to appoint emperors away from the army. Religious legitimization elevated Diocletian and Maximian above potential rivals in a way military power and dynastic claims could not.
Conflict with Sarmatia and Persia
After his acclamation, Maximian was dispatched to fight the rebel Bagaudae, insurgent peasants of Gaul. Diocletian returned to the East, progressing slowly. By 2 November, he had only reached Civitas Iovia (Botivo, near Ptuj, Slovenia). In the Balkans during the autumn of 285, he encountered a tribe of Sarmatians who demanded assistance. The Sarmatians requested that Diocletian either help them recover their lost lands or grant them pasturage rights within the empire. Diocletian refused and fought a battle with them, but was unable to secure a complete victory. The nomadic pressures of the European Plain remained and could not be solved by a single war; soon the Sarmatians would have to be fought again.
Diocletian wintered in Nicomedia.[notes 3] There may have been a revolt in the eastern provinces at this time, as he brought settlers from Asia to populate emptied farmlands in Thrace. He visited Syria Palaestina the following spring, [notes 4] His stay in the East saw diplomatic success in the conflict with Persia: in 287, Bahram II granted him precious gifts, declared open friendship with the Empire, and invited Diocletian to visit him. Roman sources insist that the act was entirely voluntary.
Around the same time, perhaps in 287, Persia relinquished claims on Armenia and recognized Roman authority over territory to the west and south of the Tigris. The western portion of Armenia was incorporated into the empire and made a province. Tiridates III, Arsacid claimant to the Armenian throne and Roman client, had been disinherited and forced to take refuge in the empire after the Persian conquest of 252–53. In 287, he returned to lay claim to the eastern half of his ancestral domain and encountered no opposition. Bahram II's gifts were widely recognized as symbolic of a victory in the ongoing conflict with Persia, and Diocletian was hailed as the "founder of eternal peace". The events might have represented a formal end to Carus' eastern campaign, which probably ended without an acknowledged peace. At the conclusion of discussions with the Persians, Diocletian re-organized the Mesopotamian frontier and fortified the city of Circesium (Buseire, Syria) on the Euphrates.
Maximian made Augustus
Maximian's campaigns were not proceeding as smoothly. The Bagaudae had been easily suppressed, but Carausius, the man he had put in charge of operations against Saxon and Frankishpirates on the Saxon Shore, had, according to literary sources, begun keeping the goods seized from the pirates for himself. Maximian issued a death-warrant for his larcenous subordinate. Carausius fled the Continent, proclaimed himself Augustus, and agitated Britain and northwestern Gaul into open revolt against Maximian and Diocletian.
Far more probable, according to the archaeological evidence available, is that Carausius probably had held some important military post in Britain and had already a firm basis of power on both Britain and Northern Gaul (a coin hoard found in Rouen proves that he was in control of that mainland area at the beginning of his rebellion) and that he profited from the lack of legitimacy of the central government. Carausius strove at having his legitimacy as a junior emperor acknowledged by Diocletian: in his coinage (of far better quality than the official one, especially his silver pieces) he extolled the "concord" between him and the central power (PAX AVGGG, "the Peace of the three Augusti", read one 290 bronze piece, displaying, on the other side, Carausius together with Diocletian and Maximian, with the caption CARAVSIVS ET FRATRES SVI, "Carausius & his brothers"  ). However, Diocletian could not allow elbow room to a breakaway regional usurper following on Postumus's footprints to enter, solely on his own accord, the imperial college. So Carausius had to go.
Spurred by the crisis, on 1 April 286,[notes 5] Maximian took up the title of Augustus. His appointment is unusual in that it was impossible for Diocletian to have been present to witness the event. It has even been suggested that Maximian usurped the title and was only later recognized by Diocletian in hopes of avoiding civil war. This suggestion is unpopular, as it is clear that Diocletian meant for Maximian to act with a certain amount of independence. It may be posited, however, that Diocletian felt the need to bind Maximian closer to him, by making him his empowered associate, in order to avoid the possibility of having him striking some sort of deal with Carausius.
Maximian realized that he could not immediately suppress the rogue commander, so in 287 he campaigned solely against tribes beyond the Rhine instead. As Carausius was allied to the Franks, Maximian's campaigns could be seen as an effort to deny the separatist emperor in Britain a basis of support on the mainland. The following spring, as Maximian prepared a fleet for an expedition against Carausius, Diocletian returned from the East to meet Maximian. The two emperors agreed on a joint campaign against the Alamanni. Diocletian invaded Germania through Raetia while Maximian progressed from Mainz. Each emperor burned crops and food supplies as he went, destroying the Germans' means of sustenance. The two men added territory to the empire and allowed Maximian to continue preparations against Carausius without further disturbance. On his return to the East, Diocletian managed what was probably another rapid campaign against the resurgent Sarmatians. No details survive, but surviving inscriptions indicate that Diocletian took the title Sarmaticus Maximus after 289.
In the East, Diocletian engaged in diplomacy with desert tribes in the regions between Rome and Persia. He might have been attempting to persuade them to ally themselves with Rome, thus reviving the old, Rome-friendly, Palmyrenesphere of influence, or simply attempting to reduce the frequency of their incursions. No details survive for these events. Some of the princes of these states were Persian client kings, a disturbing fact in light of increasing tensions with the Sassanids. In the West, Maximian lost the fleet built in 288 and 289, probably in the early spring of 290. The panegyrist who refers to the loss suggests that its cause was a storm, but this might simply have been an attempt to conceal an embarrassing military defeat. Diocletian broke off his tour of the Eastern provinces soon thereafter. He returned with haste to the West, reaching Emesa by 10 May 290, and Sirmium on the Danube by 1 July 290.
Diocletian met Maximian in Milan in the winter of 290–91, either in late December 290 or January 291. The meeting was undertaken with a sense of solemn pageantry. The emperors spent most of their time in public appearances. It has been surmised that the ceremonies were arranged to demonstrate Diocletian's continuing support for his faltering colleague. A deputation from the Roman Senate met with the emperors, renewing its infrequent contact with the Imperial office. The choice of Milan over Rome further snubbed the capital's pride. But then it was already a long established practice that Rome itself was only a ceremonial capital, as the actual seat of the Imperial administration was determined by the needs of defense. Long before Diocletian, Gallienus (r. 253–68) had chosen Milan as the seat of his headquarters. If the panegyric detailing the ceremony implied that the true center of the empire was not Rome, but where the emperor sat ("...the capital of the empire appeared to be there, where the two emperors met"), it simply echoed what had already been stated by the historian Herodian in the early third century: "Rome is where the emperor is". During the meeting, decisions on matters of politics and war were probably made in secret. The Augusti would not meet again until 303.
See also: Tetrarchy
Foundation of the Tetrarchy
Some time after his return, and before 293, Diocletian transferred command of the war against Carausius from Maximian to Flavius Constantius, a former Governor of Dalmatia and a man of military experience stretching back to Aurelian's campaigns against Zenobia (272–73). He was Maximian's praetorian prefect in Gaul, and the husband to Maximian's daughter, Theodora. On 1 March 293 at Milan, Maximian gave Constantius the office of caesar. In the spring of 293, in either Philippopolis (Plovdiv, Bulgaria) or Sirmium, Diocletian would do the same for Galerius, husband to Diocletian's daughter Valeria, and perhaps Diocletian's Praetorian Prefect.[notes 6] Constantius was assigned Gaul and Britain. Galerius was initially assigned Syria, Palestine, Egypt, and responsibility for the eastern borderlands.
This arrangement is called the tetrarchy, from a Greek term meaning "rulership by four". The Tetrarchic Emperors were more or less sovereign in their own lands, and they travelled with their own imperial courts, administrators, secretaries, and armies. They were joined by blood and marriage; Diocletian and Maximian now styled themselves as brothers. The senior Co-Emperors formally adopted Galerius and Constantius as sons in 293. These relationships implied a line of succession. Galerius and Constantius would become Augusti after the departure of Diocletian and Maximian. Maximian's son Maxentius and Constantius' son Constantine would then become Caesars. In preparation for their future roles, Constantine and Maxentius were taken to Diocletian's court in Nicomedia.
Demise of Carausius' breakaway Roman Empire
Just before his creation as Caesar, Constantius proceeded to cut Carausius from his base of support in Gaul, recovering Boulogne after a hotly fought siege, a success that would result in Carausius being murdered and replaced by his aide Allectus, who would hold out in his Britain stronghold for a further three years until a two-pronged naval invasion resulted in Allectus' defeat and death at the hands of Constantius' pretorian prefect Julius Asclepiodotus, during a land battle somewhere near Farnham. Constantius himself, after disembarking in the south east, delivered London from a looting party of Frankish deserters in Allectus' pay, something that allowed him to assume the role of liberator of Britain. A famous commemorative medallion depicts a personification of London supplying the victorious Constantius on horseback. with the legend REDDITOR LUCIS AETERNAE (Restorer of the eternal light). The suppression of this threat to the Tetrarchs' legitimacy allowed both Constantius and Maximian to concentrate on outside threats: by 297 Constantius was back on the Rhine and Maximian engaged in a full-scale African campaign against Frankish pirates and nomads, eventually making a triumphal entry into Carthage on 10 March 298. However, Maximian's failure to deal with Carausius and Allectus on his own had jeopardized the position of Maxentius as putative heir to his father's post as Augustus of the West, with Constantius' son Constantine appearing as a rival claimant.
Conflict in the Balkans and Egypt
Diocletian spent the spring of 293 travelling with Galerius from Sirmium (Sremska Mitrovica, Serbia) to Byzantium (Istanbul, Turkey). Diocletian then returned to Sirmium, where he would remain for the following winter and spring. He campaigned against the Sarmatians again in 294, probably in the autumn, and won a victory against them. The Sarmatians' defeat kept them from the Danube provinces for a long time. Meanwhile, Diocletian built forts north of the Danube, at Aquincum (Budapest, Hungary), Bononia (Vidin, Bulgaria), Ulcisia Vetera, Castra Florentium, Intercisa (Dunaújváros, Hungary), and Onagrinum (Begeč, Serbia). The new forts became part of a new defensive line called the Ripa Sarmatica. In 295 and 296 Diocletian campaigned in the region again, and won a victory over the Carpi in the summer of 296. Later during both 299 and 302, as Diocletian was then residing in the East, it was Galerius' turn to campaign victoriously on the Danube. By the end of his reign, Diocletian had secured the entire length of the Danube, provided it with forts, bridgeheads, highways, and walled towns, and sent fifteen or more legions to patrol the region; an inscription at Sexaginta Prista on the Lower Danube extolled restored tranquilitas to the region. The defense came at a heavy cost, but was a significant achievement in an area difficult to defend.
Galerius, meanwhile, was engaged during 291–293 in disputes in Upper Egypt, where he suppressed a regional uprising. He would return to Syria in 295 to fight the revanchist Persian empire. Diocletian's attempts to bring the Egyptian tax system in line with Imperial standards stirred discontent, and a revolt swept the region after Galerius' departure. The usurper L. Domitius Domitianus declared himself Augustus in July or August 297. Much of Egypt, including Alexandria, recognized his rule. Diocletian moved into Egypt to suppress him, first putting down rebels in the Thebaid in the autumn of 297, then moving on to besiege Alexandria. Domitianus died in December 297, by which time Diocletian had secured control of the Egyptian countryside. Alexandria, however, whose defense was organized under Domitianus' former correctorAurelius Achilleus, was to hold out until a later date, probably March 298.
Bureaucratic affairs were completed during Diocletian's stay: a census took place, and Alexandria, in punishment for its rebellion, lost the ability to mint independently. Diocletian's reforms in the region, combined with those of Septimius Severus, brought Egyptian administrative practices much closer to Roman standards. Diocletian travelled south along the Nile the following summer, where he visited Oxyrhynchus and Elephantine. In Nubia, he made peace with the Nobatae and Blemmyes tribes. Under the terms of the peace treaty Rome's borders moved north to Philae and the two tribes received an annual gold stipend. Diocletian left Africa quickly after the treaty, moving from Upper Egypt in September 298 to Syria in February 299. He met with Galerius in Mesopotamia.
War with Persia
See also: Roman relations with the Parthians and Sassanids and Roman–Persian Wars
In 294, Narseh, a son of Shapur who had been passed over for the Sassanid succession, came to power in Persia. Narseh eliminated Bahram III, a young man installed in the wake of Bahram II's death in 293. In early 294, Narseh sent Diocletian the customary package of gifts between the empires, and Diocletian responded with an exchange of ambassadors. Within Persia, however, Narseh was destroying every trace of his immediate predecessors from public monuments. He sought to identify himself with the warlike kings Ardashir (r. 226–41) and Shapur I (r. 241–72), who had defeated and imprisoned Emperor Valerian (r. 253–260) following his failed invasion of the Sasanian Empire.
Narseh declared war on Rome in 295 or 296. He appears to have first invaded western Armenia, where he seized the lands delivered to Tiridates in the peace of 287. Narseh moved south into Roman Mesopotamia in 297, where he inflicted a severe defeat on Galerius in the region between Carrhae (Harran, Turkey) and Callinicum (Raqqa, Syria) (and thus, the historian Fergus Millar notes, probably somewhere on the Balikh River). Diocletian may or may not have been present at the battle, but he quickly divested himself of all responsibility. In a public ceremony at Antioch, the official version of events was clear: Galerius was responsible for the defeat; Diocletian was not. Diocletian publicly humiliated Galerius, forcing him to walk for a mile at the head of the Imperial caravan, still clad in the purple robes of the Emperor.[notes 7]
Galerius was reinforced, probably in the spring of 298, by a new contingent collected from the empire's Danubian holdings. Narseh did not advance from Armenia and Mesopotamia, leaving Galerius to lead the offensive in 298 with an attack on northern Mesopotamia via Armenia.[notes 8] It is unclear if Diocletian was present to assist the campaign; he might have returned to Egypt or Syria.[notes 9] Narseh retreated to Armenia to fight Galerius' force, to Narseh's disadvantage; the rugged Armenian terrain was favorable to Roman infantry, but not to Sassanid cavalry. In two battles, Galerius won major victories over Narseh. During the second encounter, Roman forces seized Narseh's camp, his treasury, his harem, and his wife. Galerius continued moving down the Tigris, and took the Persian capital Ctesiphon before returning to Roman territory along the Euphrates.
Narseh sent an ambassador to Galerius to plead for the return of his wives and children in the course of the war, but Galerius dismissed him. Serious peace negotiations began in the spring of 299. The magister memoriae (secretary) of Diocletian and Galerius, Sicorius Probus, was sent to Narseh to present terms. The conditions of the resulting Peace of Nisibis were heavy: Armenia returned to Roman domination, with the fort of Ziatha as its border; Caucasian Iberia would pay allegiance to Rome under a Roman appointee; Nisibis, now under Roman rule, would become the sole conduit for trade between Persia and Rome; and Rome would exercise control over the five satrapies between the Tigris and Armenia: Ingilene, Sophanene (Sophene), Arzanene (Aghdznik), Corduene (Carduene), and Zabdicene (near modern Hakkâri, Turkey). These regions included the passage of the Tigris through the Anti-Taurus range; the Bitlis pass, the quickest southerly route into Persian Armenia; and access to the Tur Abdin plateau.
A stretch of land containing the later strategic strongholds of Amida (Diyarbakır, Turkey) and Bezabde came under firm Roman military occupation. With these territories, Rome would have an advance station north of Ctesiphon, and would be able to slow any future advance of Persian forces through the region. Many cities east of the Tigris came under Roman control, including Tigranokert, Saird, Martyropolis, Balalesa, Moxos, Daudia, and Arzan – though under what status is unclear. At the conclusion of the peace, Tiridates regained both his throne and the entirety of his ancestral claim. Rome secured a wide zone of cultural influence, which led to a wide diffusion of Syriac Christianity from a center at Nisibis in later decades, and the eventual Christianization of Armenia.
Further information: Diocletianic Persecution
At the conclusion of the Peace of Nisibis, Diocletian and Galerius returned to Syrian Antioch. At some time in 299, the emperors took part in a ceremony of sacrifice and divination in an attempt to predict the future. The haruspices were unable to read the entrails of the sacrificed animals and blamed Christians in the Imperial household. The emperors ordered all members of the court to perform a sacrifice to purify the palace. The emperors sent letters to the military command, demanding the entire army perform the required sacrifices or face discharge. Diocletian was conservative in matters of religion, a man faithful to the traditional Roman pantheon and understanding of demands for religious purification, but Eusebius, Lactantius and Constantine state that it was Galerius, not Diocletian, who was the prime supporter of the purge, and its greatest beneficiary. Galerius, even more devoted and passionate than Diocletian, saw political advantage in the politics of persecution. He was willing to break with a government policy of inaction on the issue.
Antioch was Diocletian's primary residence from 299 to 302, while Galerius swapped places with his Augustus on the Middle and Lower Danube. Diocletian visited Egypt once, over the winter of 301–2, and issued a grain dole in Alexandria. Following some public disputes with Manicheans, Diocletian ordered that the leading followers of Mani be burnt alive along with their scriptures. In a 31 March 302 rescript from Alexandria, he declared that low-status Manicheans must be executed by the blade, and high-status Manicheans must be sent to work in the quarries of Proconnesus (Marmara Island, Turkey) or the mines of Phaeno in southern Palestine. All Manichean property was to be seized and deposited in the imperial treasury. Diocletian found much to be offended by in Manichean religion: its novelty, its alien origins, the way it corrupted the morals of the Roman race, and its inherent opposition to long-standing religious traditions. Manichaeanism was also supported by Persia at the time, compounding religious dissent with international politics. Excepting Persian support, the reasons he disliked Manichaenism were equally applicable, if not more so, to Christianity, his next target.
Diocletian returned to Antioch in the autumn of 302. He ordered that the deaconRomanus of Caesarea have his tongue removed for defying the order of the courts and interrupting official sacrifices. Romanus was then sent to prison, where he was executed on 17 November 303. Diocletian believed that Romanus of Caesarea was arrogant, and he left the city for Nicomedia in the winter, accompanied by Galerius. According to Lactantius, Diocletian and Galerius entered into an argument over imperial policy towards Christians while wintering at Nicomedia in 302. Diocletian argued that forbidding Christians from the bureaucracy and military would be sufficient to appease the gods, but Galerius pushed for extermination. The two men sought the advice of the oracle of Apollo at Didyma. The oracle responded that the impious on Earth hindered Apollo's ability to provide advice. Rhetorically Eusebius records the Oracle as saying "The just on Earth..." These impious, Diocletian was informed by members of the court, could only refer to the Christians of the empire. At the behest of his court, Diocletian acceded to demands for universal persecution.
On 23 February 303, Diocletian ordered that the newly built church at Nicomedia be razed. He demanded that its scriptures be burned, and seized its precious stores for the treasury. The next day, Diocletian's first "Edict against the Christians" was published. The edict ordered the destruction of Christian scriptures and places of worship across the empire, and prohibited Christians from assembling for worship. Before the end of February, a fire destroyed part of the Imperial palace. Galerius convinced Diocletian that the culprits were Christians, conspirators who had plotted with the eunuchs of the palace. An investigation was commissioned, but no responsible party was found. Executions followed anyway, and the palace eunuchs Dorotheus and Gorgonius were executed. One individual, Peter Cubicularius, was stripped, raised high, and scourged. Salt and vinegar were poured in his wounds, and he was slowly boiled over an open flame. The executions continued until at least 24 April 303, when six individuals, including the bishopAnthimus, were decapitated. A second fire occurred sixteen days after the first. Galerius left the city for Rome, declaring Nicomedia unsafe. Diocletian would soon follow.
Although further persecutionary edicts followed, compelling the arrest of the Christian clergy and universal acts of sacrifice, the persecutionary edicts were ultimately unsuccessful; most Christians escaped punishment, and pagans too were generally unsympathetic to the persecution. The martyrs' sufferings strengthened the resolve of their fellow Christians. Constantius and Maximian did not apply the later persecutionary edicts, and left the Christians of the West unharmed. Galerius rescinded the edict in 311, announcing that the persecution had failed to bring Christians back to traditional religion. The temporary apostasy of some Christians, and the surrendering of scriptures, during the persecution played a major role in the subsequent Donatist controversy. Within twenty-five years of the persecution's inauguration, the Christian Emperor Constantine would rule the empire alone. He would reverse the consequences of the edicts, and return all confiscated property to Christians. Under Constantine's rule, Christianity would become the empire's preferred religion. Diocletian was demonized by his Christian successors: Lactantius intimated that Diocletian's ascendancy heralded the apocalypse, and in Serbian mythology, Diocletian is remembered as Dukljan, the adversary of God.
Illness and abdication
Diocletian entered the city of Rome in the early winter of 303. On 20 November, he celebrated, with Maximian, the twentieth anniversary of his reign (vicennalia), the tenth anniversary of the tetrarchy (decennalia), and a triumph for the war with Persia. Diocletian soon grew impatient with the city, as the Romans acted towards him with what Edward Gibbon, following Lactantius, calls "licentious familiarity". The Roman people did not give enough deference to his supreme authority; it expected him to act the part of an aristocratic ruler, not a monarchic one. On 20 December 303, Diocletian cut short his stay in Rome and left for the north. He did not even perform the ceremonies investing him with his ninth consulate; he did them in Ravenna on 1 January 304 instead. There are suggestions in the Panegyrici Latini
The Metropolitan Museum of Art
Heilbrunn Timeline of Art History
See works of art
Heilbrunn Timeline of Art History
The Temple of Dendur
Wall painting on black ground: Aedicula with small landscape, from the imperial villa at Boscotrecase
Marble lid of a cinerary chest
Marble statue of a togatus (man wearing a toga)
Bronze water spouts in the form of lion masks
Marble cinerary chest with lid
Terret (Rein Guide)
Marble sarcophagus with garlands and the myth of Theseus and Ariadne
Marble cinerary urn
Marble bust of a bearded man
Mosaic floor panel
Portrait of the Boy Eutyches
Beryl intaglio with portrait of Julia Domna
Marble portrait of the emperor Caracalla
Marble sarcophagus with the Triumph of Dionysos and the Seasons
Marble sarcophagus with the contest between the Muses and the Sirens
Gravestone with funerary banquet
Figure of Isis-Aphrodite
Box with Sleeping Eros
Marble portrait head of the Emperor Constantine I
Gold Solidus of Constantine II
Bowl Fragments with Menorah, Shofar, and Torah Ark
© 2000–2018 The Metropolitan Museum of Art