Trajan wrote an account of his campaigns as Commentaries, just like those written by Julius Caesar. However, only a single line from this has survived. Nothing at all has survived directly from the many other accounts celebrating the victories, or from narratives of the earlier campaigns under the Emperor Domitian. All we have are a handful of fragments, and the only remotely complete account is provided by writers of the Byzantine period, who summarised the fuller account written by the senator Cassius Dio in the early third century AD. What we have is brief and at times confused and we have no real idea how much fuller or reliable the original was.

Thus the Dacian Wars, for all their scale and importance, are very poorly known. Archaeology helps to a degree, not least in giving more sense of Dacian society, culture and the sophistication of their architecture, as well as the establishment of Roman forts and subsequently cities. Excavation is rarely suited to helping us to understand the faster moving events of individual campaigns and instead reveals longer term trends. At fort sites, attention naturally focuses on the later, more permanent phases of occupation, usually built in stone, rather than the initial establishment of a base. Trajan’s Column clearly tells a detailed story, presenting the official line and quite possibly representing in art many of the incidents Trajan had described in his Commentaries. Yet it is rather like trying to understand the Bayeux Tapestry, but without the captions and with very skimpy knowledge of the history of 1066.

This is even more true of the fascinating monuments at Tropaeum Traiani (modern Adamklissi in Romania, not far from the Black Sea). Dedicated to Mars Ultor – Rome’s war god Mars in his role as the avenger – these include an altar and a cenotaph, a memorial to the ‘bravest of men’ who fell, presumably during one of the conflicts with the Dacians and their allies. (Among the units listed is one from Britannia, which might well make this the first extant memorial to British soldiers.) On the great drum-shaped Tropaeum itself, there were sculptures of captives, and a row of scenes or metopes depicting battle scenes, where Roman legionaries and auxiliary infantry and cavalry parade and fight against barbarians until these are killed or captured. There is a story in these images, but we do not know what it is, in part because we do not even know the original sequence of the metopes, let alone the precise date of the incidents depicted.

The cenotaph has the space for some 3,800 names, but is badly eroded so that most of it is illegible. The first man listed was a praefectus or prefect, and while his name is lost, it states that he was born in Pompeii, but now resident in Neapolis (Naples), which means that he died sometime after the eruption of Vesuvius. Some scholars believe that the names are those of men who fell in a great disaster, perhaps one of the two major defeats suffered under Domitian. So many fatalities make it highly unlikely that the monument commemorated a hard-fought victory, but that leaves the possibility that it includes the names of all the men who had died during the course of one or both of the Dacian Wars. As with so much concerning the period, we simply do not know. The sculptures give a better idea of the true appearance of the peoples of the region and also what Roman troops looked like in the field.