|13th Emperor of the Roman Empire|
Marble bust of Trajan.
|Reign||28 January 98 – 9 August 117|
|Full name||Marcus Ulpius Traianus
(from birth to adoption);
Caesar Marcus Ulpius Nerva Traianus (from adoption to accession);
Imperator Caesar Nerva Traianus Divi Nervae filius Augustus (as emperor)
|Born||18 September 53|
|Died||9 August 117(aged 63)|
|Place of death||Selinus, Cilicia|
|Buried||Rome (ashes in foot
of Trajan's Column, now lost)
|Father||Marcus Ulpius Traianus|
Trajan (English pronunciation: //; Latin: Imperator Caesar Nerva Traianus Divi Nervae filius Augustus; 18 September 53 – 9 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 ("[be] 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
- 3 Death and succession
- 4 Building activities
- 5 Trajan's legacy
- 6 Nerva–Antonine family tree
- 7 Notes
- 8 References and further reading
- 9 External links
Early life and rise to power
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 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. According to the Augustan History, it was the future Emperor Hadrian who brought word to Trajan of his adoption. When Nerva died on 27 January 98, the highly respected Trajan succeeded without incident.
The new Roman emperor was greeted by the people of Rome with great enthusiasm, which he justified by governing well and without the bloodiness that had marked Domitian's reign. He freed many people who had been unjustly imprisoned 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".
Conquest of Dacia
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.
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. Trajan's troops were mauled in the encounter, however and he put off further campaigning for the year to let the troops heal, reinforce, and regroup.
During the following winter, King Decebalus launched a counter-attack across the Danube further downstream, but this was repulsed. Trajan's army advanced further into Dacian territory and forced King Decebalus to submit to him a year later.
Trajan returned to Rome in triumph and was granted the title Dacicus Maximus. The victory was celebrated by the Tropaeum Traiani. Decebalus, though, after being left to his own devices, in 105 undertook an invasion against Roman territory by attempting to stir up some of the tribes north of the river against the empire.
Trajan took to the field again and after building, with the design of Apollodorus of Damascus, his massive bridge over the Danube, he conquered part of Dacia in 106. After a fierce campaign (see also Second Dacian War), the Dacian capital, Sarmizegetusa Regia, was destroyed. Decebalus fled but, rather than being captured by the Roman cavalry, committed suicide, and his severed head was exhibited in Rome on the steps leading up to the Capitol. Trajan built a new city, Colonia Ulpia Traiana Augusta Dacica Sarmizegetusa, on another site than the previous Dacian Capital, although bearing the same full name, Sarmizegetusa.
Trajan also reformed the infrastructure of the Iron Gates region of the Danube. Built around 103 to 105, Trajan's Bridge, or Pontes, is considered an architectural marvel, at 3,500 feet across. 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. Trajan resettled Dacia with Romans and annexed it as a province of the Roman Empire. Trajan's Dacian campaigns benefited the Empire's finances through the acquisition of Dacia's gold mines. The victory has been commemorated by the construction of Trajan's Column, which depicts in stone carved basreliefs the Dacian Wars' most important moments.
Annexation of Nabataea
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).
Period of peace
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.
War against Parthia
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. Trajan's decision to wage war against Parthia may have had economic motives: Charax on the Persian Gulf was the sole remaining western terminus of the Indian trade route outside Roman control. Trajan began his Mesopotamian campaign in 115 BC. He marched 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. It is said he traveled with his men on foot and forded rivers.
Other historians reject this motive, seeing the campaign as triggered by the lure of territorial annexation and prestige, the motive ascribed by Cassius Dio. Other modern historians, however, think that Trajan's original aim was 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.
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) 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. The chronology of subsequent events is uncertain, but it's generally believed that early in 115 Trajan turned south into the core Parthian hegemony, taking the Northern Mesopotamian cities of Nisibis and Batnae and organizing a province of Mesopotamia in the beginning of 116, when coins were issued announcing that Armenia and Mesopotamia had been put under the authority of the Roman people.
In early 116, however, Trajan began to toy with the conquest of the whole of Mesopotamia, an overambitious goal that eventually backfired on the results of his entire campaign: 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, then dragged his fleet overland into the Tigris, 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. 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.
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, imperilled Roman positions in Mesopotamia and Armenia, something Trajan sought to deal with by forsaking direct Roman rule in Parthia proper, at least partially.
Later in 116, after defeating a Parthian army in a battle where Sanatrukes was killed and re-taking Seleucia, he formally deposed the Parthian king Osroes I and put his own puppet ruler Parthamaspates on the throne. That done, he retreated North in order to retain what he could of the new provinces of Armenia 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 rose up in rebellion once more, as did the people of Mesopotamia. 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 the high ranking legate and governor of Judaea, Lusius Quietus, who in early 116 had been in charge of the Roman division who had recovered Nisibis and Edessa from the rebels.
Quietus was promised a consulate in the following year (118) for his victories but he was murdered before this could occur. It has been theorized that Quietus was executed on the orders of the new emperor, Hadrian, for fear of Quietus' popular standing with the army and his close connections to Trajan.
Death and succession
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 9 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.
Hadrian's first act as emperor was to abandon the distant and indefensible Mesopotamia and restore Armenia — as well as Osroene – 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.
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.
Nerva–Antonine family tree
- (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)
- Trajan's regal name had an equivalent English meaning of "Commander Caesar Nerva Trajan, son of the Divine Nerva, the Emperor"
- Julian Bennett, Trajan: Optimus Princeps, 2nd Edition, Routledge 2000, 12.
- Benett, Julian (1997). Trajan. Optimus Princeps. Routledge, pp. 30–31
- Nelson, Eric (2002). Idiots guide to the Roman Empire. Alpha Books. pp. 207–209. ISBN 0-02-864151-5.
- Syme, Tacitus, 30–44; PIR Vlpivs 575
- Arnold Blumberg, "Great Leaders, Great Tyrants? Contemporary Views of World Rulers who Made History", 1995, Greenwood Publishing Group, p.315: "Trajan is frequently but misleadingly designated the first provincial emperor, because the Ulpii were from Baetica (southern Spain). The family, resident in Spain for some time, originated in Italian Tuder, not far from the Flavian home of Reate. The emperor's father, M. Ulpius Traianus, was an early adherent of Vespasian and perhaps the old family friend. This Trajan evidently married a Marcia (her name is inferred from that of their daughter Marciana) whose family owned brickyards in the vicinity of Ameria, near both Reate and Tuder. She was possibly an older sister of Marcia Furnilla, second wife of Vespasian's son Titus. Further, Ulpia, sister of the senior Trajan, was a grandmother of Hadrian. In other words, the emperor Trajan was succeeded in 117 by his cousin, member of another Italian family resident in Baetica."
- Goldsworthy, Adrian (2003). In the name of Rome: The men who won the Roman Empire. London: Weidenfeld & Nicolson. p. 320.
- Goldsworthy, Adrian (2003). In the name of Rome: The men who won the Roman Empire. London: Weidenfeld & Nicolson. p. 322.
- Augustan History, Life of Hadrian 2.5–6.
- Julian Bennett, Trajan: Optimus Princeps, London, 1997
- Bernard W. Henderson, "Five Roman Emperors" (1927).
- F. A. Lepper, "Trajan's Parthian War" (1948).
- "De Imperatoribus Romanis". An Online Encyclopedia of Roman Emperors. Retrieved 2007-07-21. "Battle of Sarmizegetusa (Sarmizegetuza), A.D. 105. During Trajan's reign one of the most important Roman successes was the victory over the Dacians. The first important confrontation between the Romans and the Dacians had taken place in the year 87 and was initiated by Domitian. The praetorian prefect Cornelius Fuscus led five or six legions across the Danube on a bridge of ships and advanced towards Banat (in Romania). The Romans were surprised by a Dacian attack at Tapae (near the village of Bucova, in Romania). Legion V Alaude was crushed and Cornelius Fuscus was killed. The victorious Dacian general was originally known as Diurpaneus (see Manea, p.109), but after this victory he was called Decebalus (the brave one)."
- "De Imperatoribus Romanis". An Online Encyclopedia of Roman Emperors. Retrieved 2007-11-08. "Because the Dacians represented an obstacle against Roman expansion in the east, in the year 101 the emperor Trajan decided to begin a new campaign against them. The first war began on 25 March 101 and the Roman troops, consisting of four principal legions (X Gemina , XI Claudia , II Traiana Fortis, and XXX Ulpia Victrix), defeated the Dacians."
- "De Imperatoribus Romanis". An Online Encyclopedia of Roman Emperors. Retrieved 2007-11-08. "Although the Dacians had been defeated, the emperor postponed the final siege for the conquering of Sarmizegetuza because his armies needed reorganization. Trajan imposed on the Dacians very hard peace conditions: Decebalus had to renounce claim to some regions of his kingdom, including Banat, Tara Hategului, Oltenia, and Muntenia in the area south-west of Transylvania. He had also to surrender all the Roman deserters and all his war machines. At Rome, Trajan was received as a winner and he took the name of Dacicus, a title that appears on his coinage of this period. At the beginning of the year 103 A.D., there were minted coins with the inscription: IMP NERVA TRAIANVS AVG GER DACICVS."
- "De Imperatoribus Romanis". An Online Encyclopedia of Roman Emperors. Retrieved 2007-11-08. "However, during the years 103–105, Decebalus did not respect the peace conditions imposed by Trajan and the emperor then decided to destroy completely the Dacian kingdom and to conquer Sarmizegetuza.he died"
- Wiseman, James 1997 "Beyond the Danube's Iron Gates." Archaeology 50(2): 24–9.
- Šašel, Jaroslav. 1973 "Trajan's Canal at the Iron Gate." The Journal of Roman Studies. 63:80–85.
- Bennett, Trajan, 177
- Bennett, Trajan, 172–182
- "Tulane University "Roman Currency of the Principate"". Tulane.edu. Retrieved 2011-12-05.
- M.I. Finley, Ancient Economy, 201/203
- Bennett, J. Trajan: Optimus Princeps. 1997. Fig. 1
- Christol & Nony, Rome, 171
- Sheldon, Rose Mary (2010). Rome's Wars in Parthia: Blood in the Sand. London: Vallentine Mitchell. p. 133.
- Finley, Ancient Economy, 158
- Quoted by Bennett, Trajan, 188
- Luttvak, Grand Strategy, 108
- Bennett, Trajan, 194–195
- Bennett, Trajan, 196; Christol & Nony, Rome,171
- Bennett, Trajan, 197/199
- Bennett, Trajan, 199
- Luttvak, Grand Strategy, 110
- Bennett, Trajan, 200
- Histoire des Juifs, Troisième période, I – Chapitre III – Soulèvement des Judéens sous Trajan et Adrien
- Bennett, Trajan, 203
- Bennett, Trajan, 201
- Butler, A. J. (1914). Babylon of Egypt: A study in the history of Old Cairo. Oxford: Clarendon Press. p. 5.
- Dio Cassius, Epitome of Book 6; 21.2–3
References and further reading
- Ancel, R. Manning. "Soldiers." Military Heritage. December 2001. Volume 3, No. 3: 12, 14, 16, 20 (Trajan, Emperor of Rome).
- Bennett, J. Trajan: Optimus Princeps, 2nd Edition, Bloomington: Indiana University Press 2001, ISBN 0-253-21435-1
- Bowersock, G.W. Roman Arabia, Harvard University Press, 1983
- Christol, M. & Nony, N. Rome et son Empire, Paris: Hachette, 2003, ISBN 2-01-145542-1
- Finley, M.I. The Ancient Economy, Berkeley: University of California Press, 1999, ISBN 0-520-21946-5
- Fuller, J.F.C. A Military History of the Western World. Three Volumes. New York: Da Capo Press, Inc., 1987 and 1988.
- v. 1. From the late times to the Battle of Lepanto; ISBN 0-306-80304-6: 255, 266, 269, 270, 273 (Trajan, Roman Emperor).
- Isaac, B. The Limits of Empire, The Roman Army in the East, Revised Edition, Oxford University Press, 1990
- Kennedy, D. The Roman Army in Jordan, Revised Edition, Council for British Research in the Levant, 2004
- Lepper, F.A. Trajan's Parthian War. London: Oxford University Press, 1948. OCLC 2898605 Also available online.
- Luttvak, Edward N. The Grand Strategy of the Roman Empire: From the First Century A.D. to the Third, Baltimore: Johns Hopkins University Press, 1979, ISBN 0-8018-2158-4
- (French) Minaud, Gérard, Les vies de 12 femmes d’empereur romain - Devoirs, Intrigues & Voluptés , Paris, L’Harmattan, 2012, ch. 6, La vie de Plotine, femme de Trajan, p. 147-168. ISBN 978-2-336-00291-0.
- Wildfeuer, C.R.H. Trajan, Lion of Rome: the Untold Story of Rome's Greatest Emperor, Aquifer Publishing, 2009. ISBN 0-981-84606-8 OCLC 496004778 Historical fiction.
- Cassius Dio, Roman History Book 68, English translation
- Aurelius Victor (attrib.), Epitome de Caesaribus Chapter 13, English translation
- Pliny the Younger, Letters, Book 10, English translation
- Benario, Herbert W. (2000). "Trajan (A.D. 98–117)". De Imperatoribus Romanis. Retrieved 2007-09-24.
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