Trajan (/ˈtreɪdʒən/; Latin: Imperator Caesar Nerva Traianus Divi Nervae filius Augustus; 18 September 53 – 8 August 117 AD) was Roman emperor from 98 AD until his death. Officially declared by the Senate as optimus princeps ("the best ruler"), Trajan is remembered as a successful soldier-emperor who presided over the greatest military expansion in Roman history, leading the empire to attain its maximum territorial extent by the time of his death. He is also known for his philanthropic rule, overseeing extensive public building programs and implementing social welfare policies, which earned him his enduring reputation as the second of the Five Good Emperors who presided over an era of peace and prosperity in the Mediterranean world.

Born into a non-patrician family of Italian origin in the city of Italica in the province of Hispania Baetica, Trajan rose to prominence during the reign of emperor Domitian. Serving as a legatus legionis in Hispania Tarraconensis, in 89 Trajan supported Domitian against a revolt on the Rhine led by Antonius Saturninus. In September 96, Domitian was succeeded by Marcus Cocceius Nerva, an old and childless senator who proved to be unpopular with the army. After a brief and tumultuous year in power, a revolt by members of the Praetorian Guard compelled him to adopt the more popular Trajan as his heir and successor. Nerva died on 27 January 98, and was succeeded by his adopted son without incident.

As a civilian administrator, Trajan is best known for his extensive public building program which reshaped the city of Rome and left multiple enduring landmarks such as Trajan''s Forum, Trajan''s Market and Trajan''s Column. Early in his reign, he annexed the Nabataean kingdom, creating the province of Arabia Petraea. His conquest of Dacia enriched the empire greatly — the new province possessed many valuable gold mines. However, the new province''s exposed position to the north of the Danube made it susceptible to attack on three sides, and it was later abandoned by Emperor Aurelian.

His war against the Parthian Empire ended with the sack of the capital Ctesiphon and the annexation of Armenia and Mesopotamia. His campaigns expanded the Roman Empire to its greatest territorial extent. In late 117, while sailing back to Rome, Trajan fell ill and died of a stroke in the city of Selinus. He was deified by the Senate and his ashes were laid to rest under Trajan''s Column. He was succeeded by his adopted son Hadrian.

As an emperor, Trajan''s reputation has endured — he is one of the few rulers whose reputation has survived nineteen centuries. Every new emperor after him was honored by the Senate with the wish felicior Augusto, melior Traiano (" luckier than Augustus and better than Trajan"). Among medieval Christian theologians, Trajan was considered a virtuous pagan, while the 18th-century historian Edward Gibbon popularized the notion of the Five Good Emperors, of which Trajan was the second.

• 1 Early life and rise to power
• 2 Roman Emperor
  • 2.1 Conquest of Dacia
  • 2.2 Annexation of Nabataea
  • 2.3 Period of peace
  • 2.4 War against Parthia
• 3 Death and succession
• 4 Building activities
• 5 Trajan''s legacy
• 6 Nerva–Antonine family tree
• 7 Notes
• 8 References and further reading
  • 8.1 Primary sources
  • 8.2 Secondary material
• 9 External links

Marcus Ulpius Traianus was born on 18 September 53 in the Roman province of Hispania Baetica (in what is now Andalusia in modern Spain), a province that was thoroughly Romanized and called southern Hispania, in the city of Italica (now in municipal area of Santiponce, in the outskirts of Seville), where the Italian families were paramount. Of Italian stock himself, Trajan is frequently but misleadingly designated the first provincial emperor.

Trajan was the son of Marcia and Marcus Ulpius Traianus, a prominent senator and general from the gens Ulpia. Marcus Ulpius Traianus the elder served Vespasian in the first Jewish war, commanding the X Fretensis legion. Trajan himself was just one of many well-known Ulpii in a line that continued long after his own death. His elder sister was Ulpia Marciana and his niece was Salonina Matidia. The patria of the Ulpii was Italica, in Spanish Baetica, where their ancestors had settled late in the 3rd century BC. During his tenure in Pannonia, he fought against the Suebic tribes in Germania. Under Nerva''s rule, Trajan was one of the most gifted generals.

As a young man, he rose through the ranks of the Roman army, serving in some of the most contentious parts of the Empire''s frontier. In 76–77, Trajan''s father was Governor of Syria (Legatus pro praetore Syriae), where Trajan himself remained as Tribunus legionis.

In about 86, Trajan''s cousin P. Aelius Afer died, leaving his young children Hadrian and Paulina orphans. Trajan and a colleague of his, Publius Acilius Attianus, became co-guardians of the two children, raising them in their respective households.

Around 91, Trajan was nominated as Consul, and brought Apollodorus of Damascus with him to Rome. Around this time also, he married Pompeia Plotina, a noble woman from the settlement at Nimes, although the marriage ultimately remained childless. It is not clear that Trajan was actively predisposed towards homosexuality, as bisexual activity was common among Roman men of the period, and so his homosexual activities could be interpreted as nothing more than a functional aspect of his class. Nevertheless, Dio Cassius makes reference to them, and his identified lovers included Hadrian and the pages of the imperial household, the actor Pylades, a dancer called Apolaustus, and possibly Licinius Sura and Nerva.

Along the Rhine River, he took part in the Emperor Domitian''s wars while under Domitian''s successor, Nerva, who was unpopular with the army - and who had just been forced by his Praetorian Prefect Casperius Aelianus to execute Domitian''s killers - needed to do something to gain their support. He accomplished this by naming Trajan as his adoptive son and successor in the summer of 97. Actually, there are hints in contemporary literary sources that Trajan''s adoption was imposed on Nerva (and Pliny the Younger wrote, that, although an emperor could not be coerced into doing something, if this were the way in which Trajan was raised to power, then it was worth it). In this case, Trajan would be actually an usurper, and the notion of a natural continuity between Nervas''s and Trajan''s reigns, therefore, an ex post fiction developed later by historians such as Tacitus

According to the Augustan History, it was the future Emperor Hadrian who brought word to Trajan of his adoption. Hadrian was retained on the Rhine frontier by Trajan as a military tribune, becoming privy to the circle of friends and relations with which Trajan hedged himself - among them, the then governor of Germania Inferior , the Spaniard Lucius Licinius Sura, who would become Trajan''s chief personal adviser and official friend. As a token of his influence, Sura would later become consul for the third time in 107; some Ancient sources also tell about him having built a bath named after him on the Aventine Hill - or having this bath built by Trajan and then named after him - on either case, a signal honor, the only exception to the established rule that a public building in the Roman Empire could be dedicated only to a member of the imperial family These baths were later expanded by the Third Century emperor Decius as a means of stressing his purported identity with Trajan. Sura is also described as telling Hadrian in 108 about his choice as imperial heir. According to a modern historian, Sura''s role as kingmaker and grey eminence was deeply resented by some senators, specially the historian Tacitus, who acknowledged Sura''s military and oratory virtues, but at the same time resented his rapacity and devious ways, similar to those of Vespasian''s grey eminence Licinius Mucianus.

When Nerva died on 27 January 98, Trajan succeeded without any outward incident. However, the fact that he chose not to hasten towards Rome, but instead to make a lengthy tour of inspection on the Rhine and Danube frontiers hints to the possible fact that his power position in Rome was unsure and that he had to assure himself first of the loyalty of the armies at the front. It is noteworthy that Trajan ordered Prefect Aelianus to attend him in Germany, where he was apparently executed ("put out of the way"), with his post being taken by Attius Suburanus. Trajan''s accession, therefore, would qualify more as a successful coup than an orderly succession.

On his entry at Rome, Trajan granted the plebs a direct gift of money. The traditional donative to the troops, however, was reduced by half. There remained the issue of the strained relations between the emperor and the Senate, specially after the supposed bloodiness that had marked Domitian''s reign and his dealings with the Curia. By playing on the motif of his feigned reluctance to hold power, Trajan was able to start building a consensus around him in the Senate. His belated ceremonial entry into Rome in 99 was notably low-key, something on which Pliny the Younger elaborated.

Also, by not supporting openly Domitian''s preference for equestrian officers, Trajan appeared as conforming to the idea (developed by Pliny) that an emperor derived his legitimacy from his adherence to traditional senatorial morals and traditional hierarchies. Therefore, he could point to the allegedly republican character of his rule. In the inaugural for his third consulship, on 1 January 100, Trajan would exhort the Senate to share with him the care-taking of the Empire - an event later celebrated on a coin. Not that Trajan shared power in any meaningful way with the Senate: on the contrary, one of the most salient traits of his reign was his encroachment on the Senate''s sphere of authority, as when he made the senatorial provinces of Achaea and Bythinia into imperial ones in order to deal with the inordinate spending in public works by local magnates. However, in the formula developed by Pliny, Trajan was a "good" emperor in that, by himself, he approved or blamed the same things the Senate would have approved or blamed. If actually Trajan was an autocrat, nevertheless his deferential behavior towards his peers qualified him to the role of virtuous monarch. That this role was a conservative one becomes evident from Pliny''s works as well as from the orations by Dio of Prusa - who, as a Greek notable and intellectual with friends in high places - and possibly an official friend to the emperor (amicus ceasaris) - saw Trajan as a defender of the status quo. Dio, however, as a local magnate with a taste for building projects, was a target for one of Trajan''s authoritarian innovations: the setting of imperial correctores to audit civic finances. Pliny, as imperial governor of Bythinia in 110 AD, had to deal with the consequences of the financial mess wrought by Dio and his fellow civic officials.

However, Trajan ingratiated himself with Greek intellectuals by recalling to Rome many (including Dio) who had been exiled by Domitian and returned a great deal of private property that Domitian had confiscated (a process that had been begun by Nerva). His popularity was such that the Roman Senate eventually bestowed upon Trajan the honorific of optimus, meaning "the best". This title had to do mostly with Trajan''s role as benefactor, as in the case of his returning confiscated property.

It was as a military commander that Trajan is best known to history, particularly for his conquests in the Near East, but initially for the two wars against Dacia — the reduction to client kingdom (101–102), followed by actual incorporation into the Empire of the trans-Danube border group of Dacia — an area that had troubled Roman thought for over a decade with the unfavourable (and to some, shameful) peace negotiated by Domitian''s ministers with the powerful Dacian king Decebalus. According to the provisions of this treaty, Decebalus was acknowledged as rex amicus, that is, client king; nevertheless, in exchange for accepting client status, he received a generous stipend from Rome, as well as being supplied with technical experts. The fact that the Dacian kingdom - unlike the Germanic tribes - was an organized state, that could develop a network of alliances of its own therefore, made strategical considerations one of the motives for Trajan''s decision for making war on it.

In the first military campaign c. March–May 101, Trajan launched a victorious campaign into the Dacian Kingdom crossing to the northern bank of the Danube River and defeating the Dacian army at Tapae (see Second Battle of Tapae) near the Iron Gates of Transylvania. It was not a decisive victory, however: Trajan''s troops were mauled in the encounter and he put off further campaigning for the year to let the troops heal, reinforce, and regroup.

During the following winter, King Decebalus took the initiative by launching a counter-attack across the Danube further downstream, supported by Sarmatian cavalry, forcing Trajan to come to the aid of the troops in his rearguard: the Dacian invasion was repulsed after two battles in Moesia, in Nicopolis ad Istrum and Adamclisi. Trajan''s army then advanced further into Dacian territory and forced King Decebalus to submit to him a year later. Decebalus had to renounce claim to some regions of his kingdom, as well as returning all Roman runaways (most of them technical experts) and to surrender all his war machines.

Trajan returned to Rome in triumph and was granted the title Dacicus Maximus. The victory was celebrated by the Tropaeum Traiani.

Although the peace of 102 had restored him to the condition of more or less harmless client king, Decebalus, though, after being left to his own devices, began to rearm, to harbor Roman runaways anew, as well as to pressure his Western neighbors, the Iazyges Sarmatians, into allying themselves to him. In 104, he devised a failed attempt on Trajan''s life by mean of some Roman deserters, as well as helding prisoner Trajan''s legate Longinus - who eventually poisoned himself while in Decebalus'' custody. Finally, in 105, he undertook an invasion against Roman-occupied territory North of the Danube.

Prior to the campaign, Trajan had already raised two entirely new legions: II Traiana - which, however, was posted in the East, at the Syrian port of Laodicea - and XXX Ulpia Victrix, which was posted to Brigetio, in Pannonia. By 105, the concentration of Roman troops assembled in the middle and lower Danube amounted to fourteen legions (up from nine at 101) - about half of the entire Roman army. Also,with the design of Apollodorus of Damascus, he ordered the building of a massive bridge over the Danube, over which the Roman army was able to cross the Danube swiftly and in numbers, as well to send in reinforcements, even in winter when the river was not frozen enough to bear the passage of a party of soldiers. Trajan also reformed the infrastructure of the Iron Gates region of the Danube. He either commissioned the creation or enlargement of the road along the Iron Gates carved into the side of the gorge. Additionally, Trajan commissioned a canal to be built around the rapids of the Iron Gates. Evidence of this comes from a marble slab discovered near Caput Bovis, the site of a Roman fort. It can be dated to the year 101 and commemorates the building of at least one canal that went from the Kasajna tributary to at least Ducis Pratum, whose embankments were still visible until recently. However, the placement of the slab at Caput Bovis suggests that the canal extended to this point or that there was a second canal downriver of the Kasajna-Ducis Pratum one.

These costly infrastructures completed, in 105 Trajan took to the field again and conquered part of Dacia in 106. After a fierce campaign, which seems to have consisted mostly of static warfare in which the Dacians, devoid of maneuvering room, kept to their network of fortresses, which the Romans sought systematically to storm (see also Second Dacian War), the Romans tightened the grip around Decebalus'' stronghold in Sarmizegetusa Regia, which was finally taken and destroyed. Decebalus fled but, rather than being captured by the Roman cavalry, committed suicide, and his severed head, brought to Trajan by the cavalryman Tiberius Claudius Maximus, was later exhibited in Rome on the steps leading up to the Capitol and thrown on the Gemonian stairs.

Trajan built a new city, Colonia Ulpia Traiana Augusta Dacica Sarmizegetusa, on another site (North to hill citadel holding the previous Dacian Capital) although bearing the same full name, Sarmizegetusa. This capital city was conceived as a purely civilian administrative center and was provided the usual Romanized administrative apparatus (decurions aediles, etc.). Urban life in Roman Dacia seems to have been restricted to Roman colonists, mostly military veterans: there is no extant evidence for the existence in the province of peregrine cities. Native Dacians continued to live in scattered rural settlements, according to their own ways. Not all of Dacia was permanently occupied: the Roman province eventually took the form of a gigantic spearhead stretching from the Danube northwards to the Carpathians, and was intended perhaps as a basis for further expansion in Eastern Europe - which the Romans conceived to be much more "flattened", closer to the ocean, than in reality. Defense of the province was entrusted to a single legion, the XIII Gemina, stationed at Apulum, which functioned as an advanced guard that could, in case of need, strike either West or East at the Sarmatians living at the borders.

Trajan resettled Dacia with Romans and annexed it as a province of the Roman Empire. Aside from their enormous booty (over half a million slaves, according to John Lydus) Trajan''s Dacian campaigns benefited the Empire''s finances through the acquisition of Dacia''s gold mines, managed by an imperial procurator of equestrian rank (procurator aurariarum). Agricultural exploitation on the villa model, on the contrary, was poorly developed. Slave labor in the province itself seems to have been relatively undeveloped and epigraphic evidence points to work in the gold mines by mean of labor contracts (locatio conductio rei) and seasonal wage-earning.

The victory was commemorated by the construction of Trajan''s Column, which depicts in stone carved basreliefs the Dacian Wars'' most important moments.

At about the same time Rabbel II Soter, one of Rome''s client kings, died. This event might have prompted the annexation of the Nabataean kingdom, although the manner and the formal reasons for the annexation are unclear. Some epigraphic evidence suggests a military operation, with forces from Syria and Egypt. What is known is that by 107, Roman legions were stationed in the area around Petra and Bostra, as is shown by a papyrus found in Egypt. The furthest south the Romans occupied was Hegra, over 300 km south-west of Petra. The empire gained what became the province of Arabia Petraea (modern southern Jordan and north west Saudi Arabia).

The next seven years, Trajan ruled as a civilian emperor, to the same acclaim as before. It was during this time that he corresponded with Pliny the Younger on the subject of how to deal with the Christians of Pontus, telling Pliny to continue but not to use an anonymous list in the interests of justice. He built several new buildings, monuments and roads in Italia and his native Hispania. His magnificent complex in Rome raised to commemorate his victories in Dacia (and largely financed from that campaign''s loot)—consisting of a forum, Trajan''s Column, and Trajan''s Market still stands in Rome today. He was also a prolific builder of triumphal arches, many of which survive, and rebuilder of roads (Via Traiana and Via Traiana Nova).

In 107 he devalued the Roman currency. He decreased the silver purity of the denarius from 93.5% to 89% — the actual silver weight dropping from 3.04 grams to 2.88 grams. This devaluation, coupled with the massive amount of gold and silver carried off after Trajan''s Dacian Wars, allowed the emperor to mint a larger quantity of denarii than his predecessors.

One notable act of Trajan during this period was the hosting of a three-month gladiatorial festival in the great Colosseum in Rome (the precise date of this festival is unknown). Combining chariot racing, beast fights and close-quarters gladiatorial bloodshed, this gory spectacle reputedly left 11,000 dead (mostly slaves and criminals, not to mention the thousands of ferocious beasts killed alongside them) and attracted a total of five million spectators over the course of the festival.

Another important act was his formalisation of the Alimenta, a welfare program that helped orphans and poor children throughout Italy. It provided general funds, as well as food and subsidized education. The program was supported initially by funds from the Dacian War, and then later by a combination of estate taxes and philanthropy.

Although the system is well documented in literary sources and contemporary epigraphy, its precise aims are controversial and have generated considerable dispute between modern scholars. It is usually assumed that the program was intended to bolster citizen numbers in Italy. However, the fact that it was subsidized by means of interest payments on loans made by landowners restricted it to a small percentage of potential welfare recipients (Paul Veyne has assumed that, in the city of Veleia, only one child out of ten was an actual beneficiary) – therefore, the idea, advanced by Moses I. Finley, that the whole scheme was at most a form of random charity, a mere imperial benevolence.

In 113, he embarked on his last campaign, provoked by Parthia''s decision to put an unacceptable king on the throne of Armenia, a kingdom over which the two great empires had shared hegemony since the time of Nero some fifty years earlier.

Many modern historians consider that Trajan''s decision to wage war against Parthia might have had economic motives: Charax on the Persian Gulf was the sole remaining Western terminus of the Indian trade route outside Roman control, and such Roman control was important in order to lower import prices and to limit the supposed drain of precious metals created by the deficit in Roman trade with the Far East.

That Charax traded with the Roman Empire, there can be no doubt, as its actual connections with merchants from Palmyra at the period are well documented in contemporary Palmyrene epigraph, which tells of various Palmyrene citizens honored for holding office in Charax. Also, Charax''s rulers domains at the time possibly included the Bahrein islands (where a Palmyrene citizen held office as satrap) something which offered the possibility of extending Roman hegemony into the Persian Gulf itself. The rationale behind Trajan''s campaign, in the case, would be one of breaking down a system of Far Eastern trade through small Semitic ("Arab") cities under Parthia''s control and to put it under Roman control instead.

In his Dacian conquests, Trajan had already had resorted to Syrian auxiliary units, whose veterans, alongside with Syrian traders, had an important role in the subsequent colonization of Dacia. He had recruited Palmyrene units into his army, including a camel unit - therefore apparently procuring Palmyrene support to his ultimate goal of annexing Charax. It has even been ventured that, when earlier in his campaign Trajan annexed Armenia, he was bound to annex the whole of Mesopotamia, lest the Parthians were to interrupt the flux of trade from the Persian Gulf and/or foment trouble at the Roman frontier on the Danube.

Other historians reject these motives, as the supposed Parthian "control" over the maritime Far Eastern trade route was, at best, conjectural and based on a selective reading of Chinese sources - trade by land through Parthia seems to have been unhampered by Parthian authorities and left solely to the devices of private enterprise. As in the case of the alimenta, scholars like Moses Finley and Paul Veyne have considered the whole idea of a foreign trade "policy" behind Trajan''s war anachronistic: the sole Roman concern with the Far Eastern luxuries trade - besides collecting toll taxes and customs - was moral and involved frowning upon the "softness" of luxuries, but no economic policy.

The alternative view is to see the campaign as triggered by the lure of territorial annexation and prestige, the sole motive ascribed by Cassius Dio. Also, there was the propaganda value of an Eastern conquest that would emulate, in Roman fashion, those of Alexander the Great. It''s possible that the attachment of Trajan to an expansionist policy was supported by a powerful circle of conservative, war hawk senators from Hispania, among them Licinius Sura.

Finally, there are other modern historians who think that Trajan''s original aims were purely military and quite modest: to assure a more defensible Eastern frontier for the Roman Empire, crossing across Northern Mesopotamia along the course of the Khabur River in order to offer cover to a Roman Armenia.

The campaign was carefully planned in advance: ten legions were concentrated in the Eastern theater; since 111, the correspondence of Pliny the Younger witnesses to the fact that provincial authorities in Bithynia had to organize supplies for passing troops and local city councils and their individual members had to shoulder part of the increased expenses by supplying troops themselves. The intended campaign, therefore, was immensely costly from its very beginning.

Trajan marched first on Armenia, deposed the Parthian-appointed king (who was afterwards murdered while kept in the custody of Roman troops in an unclear incident, later described by Fronto as a breach of Roman good faith) and annexed it to the Roman Empire as a province, receiving in passing the acknowledgement of Roman hegemony by various tribes in the Caucasus and on the Eastern coast of the Black Sea — a process that kept him busy until the end of 114. At the same time, a Roman column under the legate Lusius Quietus - an outstanding cavalry general who had signaled himself during the Dacian Wars by commanding a unit from his native Mauretania - crossed the Araxes river from Armenia into Media Atropatene and the land of the Mardians (present-day Ghilan). It''s possible that Quietus'' campaign had as its goal the extending of the newer, more defensible Roman border eastwards towards the Caspian Sea and northwards at the foothills of the Caucasus.

The chronology of subsequent events is uncertain, but it''s generally believed that early in 115 Trajan launched a Mesopotamian campaign, marching down towards the Taurus mountains in order to consolidate territory between the Tigris and Euphrates rivers. He placed permanent garrisons along the way to secure the territory. While Trajan moved from West to East, Lusius Quietus moved with his army from the Caspian Sea towards the West, both armies performing a successful pincer movement, whose apparent result was to establish a Roman presence into the core Parthian hegemony, with Trajan taking the Northern Mesopotamian cities of Nisibis and Batnae and organizing a province of Mesopotamia, including the Kingdom of Osrhoene - where King Abgaros VII submitted to Trajan publicly - as a Roman protectorate. This process seems to have been completed in the beginning of 116, when coins were issued announcing that Armenia and Mesopotamia had been put under the authority of the Roman people.

After wintering in Antioch during 115/116 - and, according to literary sources, barely escaping from a violent earthquake that claimed the life of one of the consuls of 115, M. Pedo Virgilianus - Trajan took again to the field in 116, with a view to the conquest of the whole of Mesopotamia, an overambitious goal that eventually backfired on the results of his entire campaign. As far as the sources allows a description of the campaign, it seems that one Roman division crossed the Tigris into Adiabene, sweeping South and capturing Adenystrae; a second followed the river South, capturing Babylon; while Trajan himself sailed down the Euphrates from Dura-Europus - where a triumphal arch was erected in his honour - through Ozogardana, where he erected a "tribunal" still to be seem at the time of Julian the Apostate''s campaigns in the same area. Having come to the narrow strip of land between the Euphrates and the Tigris, he then dragged his fleet overland into the latter river, capturing Seleucia and finally the Parthian capital of Ctesiphon.

He continued southward to the Persian Gulf, receiving the submission of Athambelus, the ruler of Charax, whence he declared Babylon a new province of the Empire, sent the Senate a laurelled letter declaring the war to be at a close and bemoaning that he was too old to go on any further and repeat the conquests of Alexander the Great.As Charax was a de facto independent kingdom with important connections to Palmyra, Trajan''s bid for the Persian Gulf may have coincided with Palmyrene interests in the region.

A province of Assyria was also proclaimed, apparently covering the territory of Adiabene, as well as some measures seem to have been considered about the fiscal administration of the Indian trade- or simply about the payment of customs (portoria) on goods traded on the Euphrates & Tigris According to some modern historians, Trajan might have probed into extending Roman suzerainty over the mountaineer tribes holding the passes across the Zagros Mountains into the Iranian plateau eastward, as well as establishing some sort of direct contact between Rome and the Kushan Empire.

However, as Trajan left the Persian Gulf for Babylon — where he intended to offer sacrifice to Alexander in the house where he had died in 323 BC. — a sudden outburst of Parthian resistance, led by a nephew of the Parthian king, Sanatrukes, who had retained a cavalry force, possibly strengthened by the addition of Saka archers, imperilled Roman positions in Mesopotamia and Armenia, something Trajan sought to deal with by forsaking direct Roman rule in Parthia proper, at least partially.

Trajan sent two armies towards Northern Mesopotamia: the first, under Lusius Quietus, recovered Nisibis and Edessa from the rebels. while a second, under Appius Maximus Santra (probably a governor of Macedonia), was defeated, with Santra being killed. Later in 116, Trajan defeated - assisted by Quietus and other two legates, M. Erucius Clarus and Tiberius Julius Alexander Julianus - a Parthian army in a battle where Sanatrukes was killed. After re-taking and burning Seleucia, Trajan then formally deposed the Parthian king Osroes I and put his own puppet ruler Parthamaspates on the throne. This event was commemorated in a coin so as to be presented as the reduction of Parthia to client kingdom status: "a king is given to the Parthians", Rex Parthis Data. That done, Trajan retreated North in order to retain what he could of the new provinces of Armenia - where he had already accepted an armistice in exchange for surrendering part of the territory to Sanatrukes'' son Vologeses - and Mesopotamia.

It was at this point that Trajan''s health started to fail him. The fortress city of Hatra, on the Tigris in his rear, continued to hold out against repeated Roman assaults. He was personally present at the siege and it is possible that he suffered a heat stroke while in the blazing heat.

Shortly afterwards, the Jews inside the Eastern Roman Empire, in Egypt, Cyprus and Cyrene - this last province being probably the original trouble hotspot- rose up against what probably was an outburst of religious rebellion against the local pagans, this widespread rebellion being afterwards named the Kitos War. Another rebellion flared up among the Jewish communities of Northern Mesopotamia, probably part of a general reaction against Roman occupation. Trajan was forced to withdraw his army in order to put down the revolts. Trajan saw it as simply a temporary setback, but he was destined never to command an army in the field again, turning his Eastern armies over to Lusius Quietus, who meanwhile had been made governor of Judaea and might have had to deal earlier with some kind of Jewish unrest in the province. Quietus discharged his commission successfully, so much that the war was afterward named after him - Kitus being a corruption of Quietus.

Quietus was promised a consulate in the following year (118) for his victories but he was killed before this could occur, during the bloody purge that opened Hadrian''s reign, in which Quietus and other three former consuls were sentenced to death after being tried on a vague charge of conspiracy by the (secret) court of the Praetorian Prefect Attianus. It has been theorized that Quietus and his colleagues were executed on Hadrian''s direct orders, for fear of their popular standing with the army and their close connections to Trajan. Opposedly, the next prominent Roman figure in charge of the repression, the equestrian Quintus Marcius Turbo, who had dealt with the rebel leader from Cyrene Loukuas, retained Hadrian''s trust, eventually becoming his Praetorian Prefect.

Early in 117, Trajan grew ill and set out to sail back to Italy. His health declined throughout the spring and summer of 117, something publicly acknowledged by the fact that a bronze bust displayed at the time in the public baths of Ancyra showed him clearly aged and emaciated. By the time he had reached Selinus in Cilicia which was afterwards called Trajanopolis, he suddenly died from edema on 8 August. Some say that he had adopted Hadrian as his successor, but others that it was his wife Pompeia Plotina who hired someone to impersonate him after he had died.

Aware that the Parthian campaign was an enormous setback, and that it revealed that the Roman Empire had no means for an ambitious program of conquests, Hadrian''s first act as emperor was to abandon - outwardly out of his own free will - the distant and indefensible Mesopotamia and to restore Armenia — as well as Osrhoene – to the Parthian hegemony under Roman suzerainty. However, all the other territories conquered by Trajan were retained. Trajan''s ashes were laid to rest underneath Trajan''s column, the monument commemorating his success.

Trajan was a prolific builder in Rome and the provinces, and many of his buildings were erected by the gifted architect Apollodorus of Damascus. Notable structures include Trajan''s Column, Trajan''s Forum, Trajan''s Bridge, Alcántara Bridge, the road and canal around the Iron Gates (see conquest of Dacia), and possibly the Alconétar Bridge. Some historians also attribute the construction of the Babylon fortress in Egypt to Trajan, the remains of the fort is what is now known as the Church of Mar Girgis and its surrounding buildings. In order to build his forum and the adjacent brick market that also held his name Trajan had vast areas of the surrounding hillsides leveled.

Unlike many lauded rulers in history, Trajan''s reputation has survived undiminished for nearly nineteen centuries.

Ancient sources on Trajan''s personality and accomplishments are unanimously positive. Pliny the Younger, for example, celebrates Trajan in his panegyric as a wise and just emperor and a moral man. Dio Cassius added that he always remained dignified and fair. The Christianisation of Rome resulted in further embellishment of his legend: it was commonly said in medieval times that Pope Gregory I, through divine intercession, resurrected Trajan from the dead and baptized him into the Christian faith. An account of this features in the Golden Legend.

Theologians, such as Thomas Aquinas, discussed Trajan as an example of a virtuous pagan. In the Divine Comedy, Dante, following this legend, sees the spirit of Trajan in the Heaven of Jupiter with other historical and mythological persons noted for their justice. Also a mural of Trajan stopping to provide justice for a poor widow is present in the first terrace of Purgatory as a lesson to those who are purged for being proud.

He also features in Piers Plowman. An episode, referred to as the justice of Trajan was reflected in several art works.

In the 18th century King Charles III of Spain commissioned Anton Raphael Mengs to paint The Triumph of Trajan on the ceiling of the banqueting-hall of the Royal Palace of Madrid – considered among the best work of this artist.

"Traian" is used as a male first name in present-day Romania – among others, that of the country''s current president, Traian Băsescu.

• (1) = 1st spouse
• (2) = 2nd spouse (not shown)
• (3) = 3rd spouse
• Darker purple indicates Emperor of the Nerva-Antonine dynasty; lighter purple indicates designated imperial heir of said dynasty who never reigned
• dashed lines indicate adoption; dotted lines indicate love affairs/unmarried relationships
• small caps = posthumously deified (Augusti, Augustae, or other)