Cassius Parmensis is not a name likely to feature in discussions among Donald Trump’s advisers as they consider how to deploy the outgoing president’s war chest and fan base in order to resurrect his fortunes. By the same token, one can assume that the rather more famous Roman, Scipio Africanus, is not being cited by Joe Biden’s staffers as they seek a revival of America’s fortunes. Yet I found myself reflecting on the dilemmas facing both sets of aides as I read of Parmensis and Scipio in the two latest histories to address aspects of ancient Rome.

Poet, playwright, admiral, Parmensis is one of the lesser known of the idealists, ideologues and rivals who killed Julius Caesar. The Last Assassin is a novella of a history of his 14 years on the run after that fateful Ides of March. He was the last of the assassins to evade the vengeance of Caesar’s adopted heir, Octavian. His story is not just a gripping sideways take on the tumultuous last chapter of the Roman Republic. It is also implicitly a timely reminder how to obtain and retain power, which seems all the more relevant as a successor world hegemon prepares for change at the top.

As you would expect from a distinguished former journalist, Peter Stothard knows how to deploy the telling diamond stud of a detail — whether in Senate debates, sea battles or describing the fusion of poetry and propaganda. This was a time when politicians vied to enlist top poets for their PR campaigns. Parmensis’ “scabrous satire” about Octavian’s past finds an echo in Trump’s snarling taunting of his rivals — Lyin’ Ted, Sleepy Joe, et al. But the Latin poet’s jibes, we learn, lacked the “subtlety” to thrive in a nascent age of autocracy.

The narrative also reminds us that there was nothing inevitable about Octavian’s accretion of total power — or the conspirators’ losing of it. Just as it is now easy to see that if Trump had pursued a different coronavirus strategy he might have won a second term, so Parmensis and his fellow assassins threw away a number of golden opportunities.

Stothard has woven a taut thriller from scant historical threads. But most of all this is a story of principles and the fight against tyranny, and all the better for focusing on one of history’s forgotten players. The backdrop is a power struggle that would define the future of much of Europe, north Africa and the Near East. This is also the terrain of Gladius, an account of the single greatest factor behind the remarkable longevity of Roman power: the army.

The author, Guy de la Bédoyère, has been writing on the Roman world for three decades. Here he expertly keeps himself in the shadows aware that the details and story need little authorial intervention. We hear of now long-forgotten emperors, such as Probus, who disliking indolence pushed his soldiers too far and ended up being chased up a tower and killed by them. We read of stratagems such as Roman soldiers sowing turnips to trick Carthaginians into thinking they had the wherewithal to withstand a long siege. We learn of their centuries-long perfection of planning and logistics. Readers in HR departments looking for historical buttressing of their brief, will be heartened to know that at one stage the army had individual career reviews of every soldier. (When seeking to root out troublemakers, Mark Antony supposedly consulted them.)

But it is the welter of individuals’ stories that makes Gladius such a triumph. There is Chrauttius, a legionary posted in a camp at northern Britain at the end of the 1st century AD, who wrote to a friend based in London hoping he could send him some shears. We also learn of the lives of trailing spouses at the same camp, Vindolanda, as well as tantalising glimpses of the lives of children of peripatetic military families. All these are via the same source: the hundreds of wooden leaf tablets that were preserved in Vindolanda’s waterlogged soil for nearly two millennia. Their discovery, starting in 1973, has transformed our understanding of the lives, appetites and careers of ordinary legionaries, and highlighted the potential fluidity of a career in what has traditionally and understandably been depicted as the ultimate disciplinarian’s machine.

Implicit in de la Bédoyère’s narrative, which carries you through 800 years of history, is that if you stick to fundamentals, however calamitous the defeats, however flawed individual leaders, the mission can endure. That is why I would commend it to Biden’s team. They should think of Scipio Africanus. He took over as consul after a catastrophic few years for Rome that had seen it close to being toppled from its pedestal — and when he finally left public office Rome had never been more powerful.

Biden is not Scipio. But if there is a common theme to these two riveting histories it is that great global superpowers can easily surmount the odd bout of turbulence at the top.

The Last Assassin: The Hunt for the Killers of Julius Caesar, by Peter Stothard, Weidenfeld & Nicolson, RRP£20, 274 pages

Gladius: Living, Fighting and Dying in the Roman Army, by Guy de la Bédoyère, Little, Brown, RRP£25/University of Chicago Press RRP$30, 352 pages

Alec Russell is FT Weekend editor

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