Trajan’s Dacian Wars were major conflicts, eventually resulting in the acquisition by Rome of the new province of Dacia, its heartland in modern-day Romania. Conquests on this scale were fairly rare after the death of Augustus, Rome’s first emperor, in AD 14. Rarely did a Roman emperor want to spend years off on campaign outside the empire, and even more rarely did they trust anyone else to do this for them, lest they become a dangerous rival. Trajan was one of the few exceptions and has gone down in history as a great soldier, who spent almost a third of his reign on campaign. As far as we can tell, his military record before he became emperor was fairly modest and a large part of his quest for military glory came from a desire to justify his rather weak claim to rule. Dacia, a former enemy who had inflicted several humiliating defeats on the Romans in recent memory, offered an ideal opportunity for an aggressive and glorious war.

Trajan’s First Dacian War (AD 101–102) brought victories and was widely celebrated, but left Decebalus of Dacia in charge of much of his kingdom. The Second War (AD 105–106) resulted in the abolition of the kingdom, the suicide of Decebalus, and the formal creation of the Roman province (which was subsequently divided into three provinces). Both wars required the commitment of substantial numbers of Roman troops, with perhaps a fifth or even a quarter of the entire army involved and an even higher proportion of legions contributing detachments or vexillations. Warfare on this scale was expensive, but Dacia, rich in mineral resources, especially gold, which appears to have been a royal monopoly, was a great prize.

The loot from Dacia funded the construction of Trajan’s Forum in the heart of Rome itself, enough of which is still visible to give an idea of its grand and lavish scale. At its heart was Trajan’s Column, 93’ high on a 20’ pedestal, decorated with carved reliefs telling the stories of the two wars – it was claimed that the height was to show how much earth had been excavated from the hillside to permit the construction of the complex. The sculptures are very detailed, depicting soldiers marching, parading and sacrificing, building roads and forts, and fighting battles and sieges. In most cases weapons were added as bronze miniatures, long since plundered and recycled so that apart from a few carved swords and bows, men wave empty hands at each other. Much is stylised, so that ships and buildings are shown on a smaller scale than the figures. Trajan is prominent, but depicted as only slightly larger than everyone else – this is no great king smiting his feeble foes. Legionaries are marked out as clearly distinct from the regular auxiliaries, let alone the irregulars, and everyone is dressed as an audience in Rome would expect, rather than with strict accuracy, so that the Dacians in the main are generic barbarians, with shaggy hair, beards and baggy tunics and trousers. Debate continues to rage over the accuracy of the scenes.