The City is set against the early stages of Trajan’s eastern campaigns. While it is possible to argue over the precise chronology, Trajan did go to Antioch, he did spend time making offerings in temples there and nearby, and Hadrian did accompany him on at least one of these visits, even though the story of the emperor collapsing is invented. After that, he travelled to Zeugma and then north to where a large force had concentrated for the intervention in Armenia. As described in the story, the Armenian king began by adopting a defiant stance during negotiations, but as the Romans advanced into the kingdom he backed down. On many occasions in the past kings had made formal submission to Roman commanders who then responded by making a show of restoring them to power and honour. For whatever reason, Trajan acted differently, deposing the king, who was killed in mysterious circumstances soon afterwards. Trajan’s main army then divided into several columns which pushed into neighbouring kingdoms, although only a few anecdotes are preserved about these. In one, a Roman commander issued snowshoes to his soldiers, allowing them to fight effectively in the snow of the high mountains. In another snippet, a city named Adenystrae (location unknown) was captured when a centurion and some soldiers being held in its prison managed to escape and open the gates to the besiegers, providing inspiration for Ferox’s and Sentius’ exploits at the end of our story.

There is almost no detail in our meagre sources of fighting between Roman forces and those of the Arsacid king of Parthia, although presumably a good deal of this occurred, especially when Trajan’s men advanced towards the great Parthian cities. However, it is no coincidence that the bulk of the material refers to negotiation and conflict with individual kings or cities like Hatra. Within the Roman Empire were several autonomous kingdoms, even if the number of these had fallen since the early days of the Principate. On the borders were even more of these states, while the Parthian title of king of kings was not simply an honour but a reality, for the Arsacid king was overlord of many lesser kingdoms and states. His influence, let alone control, over these varied a great deal depending on the circumstances, and the strength and ambitions of everyone involved. Scholars are apt to speak of pro-Roman or pro-Parthian monarchs in Armenia and elsewhere, simplifying what was a very complex relationship. Alliance with one empire did not necessarily mean hostility to the other, and it was perfectly possible to maintain friendly relations with both.

Most of the time, neither the Roman emperor nor the Arsacid king of Parthia wanted very much from allied kings. They favoured stability; both wanted local kings not to be hostile to them or their interests, but otherwise had no real interest in how they ran their kingdoms. Everyone benefitted from the trade that passed through these lands, especially the luxuries coming from India and ultimately China, such as silk and spices. Yet by their nature, these states tended to be unstable, for there was rarely any firm system of succession, and any member of the royal family could become ruler. This was also a problem for the Parthians, exacerbated by the practices of polygamy and the royal harem, which meant that there tended to be a lot of potential successors around. One Parthian king murdered thirty brothers to ensure his succession, and such bloodletting was not unusual. Most of the periods of friction between Rome and Parthia began with an internal power struggle in Armenia or one of the other kingdoms. This, and the wider background of Trajan’s aggressive response to concerns of this sort, provide the context for our story.