One of the joys of writing – and reading – historical fiction is the sense of tracing the thread of a single life through the broader fabric of the past, and discovering the ways that individual people are affected by historical events. To describe the experiences of one man or woman, especially in a dramatic and volatile period, and follow them over the course of a novel or a continuing series of novels, is to sense the motion of the past and the ways that the great events and towering personalities of history influence and impact human lives.

The early fourth century AD, the setting for the Twilight of Empire novels, was certainly dramatic and volatile. This was the moment when the ancient classical civilisation of Rome, already over a thousand years old, began its transformation into the Byzantine world. Over a few short decades, the Roman empire was thrown into bloody civil wars and beset by barbarian invasions. Christianity surged in power and influence, developing from an illegal and persecuted faith into the chosen religion of the emperor himself. 

But to create engaging stories and characters in a setting like this, it is necessary to look beneath the surface of events and explore the lives of those people, perhaps now forgotten by history, who made the changes possible. My protagonist, Aurelius Castus, is one such man. A career soldier, over the course of the novels he rises from the lowest ranks in the army to a position of dangerous prestige. His adventures may be exceptional, but I was eager to base them on historical reality, and in fact there were several men during this period who, like Castus, used the army as ladder to power and fame.

Until the mid-third century AD, the formidable Roman military system was commanded by men of the aristocracy, the equestrian and senatorial orders. But in the chaos towards the century’s end, this traditional structure collapsed. Instead, the officers of the army were promoted from the ranks of the centurionate. Ironically, just as the wider society was becoming increasingly hierarchical and oppressive, so the army offered a route to social advancement. Many of the emperors of this period – the great Diocletian, one of the Tetrarchic rulers who rebuilt the empire after the crisis – came from just this background. Castus, then, has his roots in a very real social phenomenon.

A protagonist so well placed, at the cutting edge of the military exploits and political machinations that were to transform the world, allows a panoramic viewpoint over the events of the era. Castus’s journey will take him from the wild frontier of northern Britain, where Constantine was first acclaimed emperor in AD306, through the disputed lands of Gaul and the Rhine frontier to the very heartland of the empire, and the city of Rome itself. He will stand in the front lines of some of the greatest battles in Roman history, including the epic clash at the Milvian Bridge, still commemorated today on the painted ceilings of the Vatican. 

But with Constantine established as sole ruler of the empire, and Christianity in the ascendant, the traditionalist Castus will find his beliefs and his loyalties severely tested. How would a man from that background, and with such a sense of loyalty to the old order, react to the reality of a changing world? This is the journey that these novels will trace, and the challenges that Castus must overcome.

- Ian Ross

Ian Ross has been researching and writing about the later Roman world and its army for over a decade. His first novel, The War at the Edge of the World, is available in hardback and ebook now.