Trajan: The Best of Emperors
The Senate’s formula for praising good emperors — felicior Augusto, melior Traiano, may you be luckier than Augustus and better than Trajan — established Trajan as the standard of imperial virtue against which all subsequent emperors were measured. He was the first provincial emperor, born in Spain to a Roman family that had settled there generations earlier, and his elevation by Nerva in 97 AD represented the completion of the process by which the Roman Empire’s leadership became genuinely imperial rather than Italian. He was admired by his contemporaries, praised by the senatorial tradition that wrote most of the surviving ancient history, and still regarded by most historians as among the most capable emperors who ever held the position. His reign was also the high-water mark of Roman territorial expansion, after which the empire never grew larger and began, slowly and then rapidly, to contract.
His military record was genuinely impressive. The Dacian Wars of 101-102 AD and 105-106 AD — two campaigns against the kingdom of Dacia in what is now Romania — produced Rome’s last major territorial annexation. The campaign was not easy; Decebalus, the Dacian king, was a capable commander who had humiliated previous Roman forces and who fortified his territory with considerable sophistication. Trajan’s campaigns required extensive engineering as well as military operations: the bridge across the Danube designed by Apollodorus of Damascus, the longest span in the ancient world, was built to supply and sustain the invasion force. Trajan’s Column in Rome, still standing, presents the entire campaign in a continuous spiral narrative of 2,500 figures that is both a victory monument and the most detailed representation of the Roman army in action that survives from antiquity.
The Dacian gold and silver that flowed into the Roman treasury after the conquest — Dacia’s mines were among the richest in Europe — funded building programs in Rome that included Trajan’s Forum, the largest forum complex in the city, and the adjacent markets that bear his name and remain the most complete surviving example of Roman commercial architecture. Trajan’s Column stands at the center of the forum, its base serving as his tomb. The scale of the investment was made possible by the Dacian wealth, and the architectural program reflected a deliberate statement of imperial power and generosity that Trajan understood was central to his political position.
His eastern campaign in 113-117 AD was more ambitious and less durable. The pretext was a dispute over Armenia, a perennial border conflict between Rome and Parthia; the scale of the campaign went far beyond any previous Roman eastern operation, resulting in the annexation of Armenia, Mesopotamia, and — briefly — Assyria. Trajan reached the Persian Gulf, reportedly lamenting that he was too old to follow Alexander further east. The conquests were real: Roman forces occupied Ctesiphon, the Parthian capital, and Trajan sailed down the Euphrates to see the sea that connected to India. They were also immediately unstable: widespread revolts broke out in the newly annexed territories simultaneously with a major Jewish revolt in the eastern provinces, and Trajan died in Cilicia in 117 AD during the difficult process of managing both crises. His successor Hadrian immediately abandoned the Mesopotamian conquests, a decision that generated controversy but which most historians have judged strategically correct.
The Panegyricus delivered by Pliny the Younger to Trajan in 100 AD is the most extended surviving example of senatorial enthusiasm for an emperor and provides a detailed portrait of what the educated Roman aristocracy valued in an imperial ruler: accessibility, modesty in the exercise of power, respect for senatorial dignity, personal participation in military hardship, and the avoidance of the paranoia and cruelty that had made Domitian’s reign a source of bitter memory. Trajan, in Pliny’s portrait, was an emperor who behaved like a first citizen rather than a master, who consulted rather than commanded, who earned obedience through respect rather than fear. Whether the portrait was accurate or idealized is difficult to determine; Pliny’s genre required a certain amount of flattery, and the Senate’s satisfaction with Trajan’s reign is consistent enough across sources to suggest he genuinely managed the relationship well.
His death left one ambiguity that troubled later commentators: the adoption of Hadrian was announced by Trajan’s wife Plotina from the deathbed in circumstances that his opponents found suspicious. Trajan had not publicly designated a successor during his reign, and the last-minute adoption — if genuine — reflected the improvised character of Roman succession even after a century of principate. Hadrian’s subsequent reign, with its abandonment of Trajan’s conquests and its more complex relationship with the Senate, made the retrospective comparison to Trajan a recurrent element of political discourse. The best emperor was always the previous one, or the one before that, which is how nostalgia always works and which says as much about human political psychology as it does about the specific men being compared.