The Colosseum was not called the Colosseum when it was built. Its official name was the Flavian Amphitheater — the Amphitheatrum Flavium — after the dynasty that commissioned and completed it. The name we use derives from a colossal bronze statue of Nero that stood nearby, a work of imperial self-aggrandizement that survived its subject by centuries. The building itself is formally anonymous, which is fitting for a structure whose purpose was to direct attention outward, toward the spectacle it contained, rather than inward toward the men who paid for it.

Isis arrived in Rome over official objections. The Roman Senate banned her worship multiple times in the first century BC — in 58, 53, 50, and 48 BC, with varying degrees of enforcement — ordering her altars demolished and her images removed from the city. The bans failed because the cult’s appeal was stronger than the official resistance, and by the first century AD the goddess who had been repeatedly expelled was being worshipped in temples funded by emperors. Caligula built her a major temple in the Campus Martius. Vespasian and Titus celebrated their triumph over Judaea in her temple precinct. Commodus appeared in her processions in priestly dress. Whatever the Senate of the Republic had thought about Egyptian divinities, the Empire had reached different conclusions.

The assassination of Julius Caesar on the Ides of March, 44 BC, has been painted repeatedly across five centuries of European art, and the accumulated versions constitute a case study in how the same historical event can be made to mean entirely different things depending on the visual choices made around it. The event is fixed: Caesar was killed in the Theater of Pompey by a group of senators. The meaning of the event — was it tyrannicide or murder, liberation or catastrophe — has been contested ever since, and the paintings rehearse that contest in visual terms.

Kevin Macdonald’s The Eagle, based on Rosemary Sutcliff’s 1954 novel The Eagle of the Ninth, occupies a different register from the gladiatorial epics and political dramas that constitute most of Hollywood’s Roman output. It is a frontier film, a journey narrative, set in Roman Britain and the territory beyond Hadrian’s Wall, and it is interested in questions that the arena films are not: what does it mean to serve an empire at its geographical and civilizational limits, and what does Rome look like from outside?

Anthony Mann’s The Fall of the Roman Empire was released in 1964, ran for nearly three hours, cost twenty million dollars, and was such a catastrophic commercial failure that it effectively ended the sword-and-sandal epic as a Hollywood genre for a generation. It also happens to be a substantially better film than its reputation suggests, more historically serious than most of its contemporaries, and in certain respects a more honest engagement with the period it depicts than the celebrated Gladiator that covered similar ground thirty-six years later.

Rome was not original in its theology, and it did not pretend to be. The Romans were systematic borrowers of divine power, operating on the practical assumption that a god who worked was worth incorporating regardless of origin. The result was a pantheon that was Greek at its core, overlaid with indigenous Italian tradition, supplemented by imports from Egypt, Persia, and Syria, and eventually contested and replaced by a monotheism that originated in Judea. Roman religion was an accumulation, not a creation.

Rome fed a significant portion of its population for free, and had been doing so, in various forms, for over five centuries by the time the Western Empire collapsed. The grain dole — the frumentatio in its Republican form, the annona in its more developed imperial incarnation — was not a welfare program in the modern sense, though it served some of the same social functions. It was a political institution, a mechanism for managing the relationship between the imperial government and the volatile urban population of the capital, and it was expensive enough, logistically complex enough, and politically significant enough to have shaped the development of Roman administration, agriculture, and provincial policy for centuries.

The city of Rome at its height had a population of somewhere between half a million and a million people — the estimates vary and the ancient census figures are difficult to interpret — compressed into an urban area that had no master plan, no grid, and no effective building code until the fires that made such codes politically possible. The vast majority of these people lived not in the marble houses of imperial imagination but in multi-story apartment buildings called insulae — islands — so called because they filled city blocks the way islands fill water, surrounded on all sides by streets. The insula was Rome’s residential reality, and it was often dangerous, frequently squalid, and occasionally catastrophically flammable.

The Pantheon is the best-preserved ancient building in the world, and it is better preserved than most medieval buildings, because it has been in continuous use since its construction. Hadrian built it between approximately 118 and 128 AD on the site of earlier temples in the Campus Martius district of Rome, and it has served as a temple, a church, a tomb, and a tourist site across nineteen centuries without the structural interruption of abandonment. The dome that spans its interior has not been surpassed in diameter — 43.3 meters — by any unreinforced concrete construction in the two thousand years since it was poured. Whatever Rome’s engineers knew, they knew something that took a very long time to recover.

The Praetorian Guard killed four emperors, elevated at least five more to power, and constituted the single most politically destabilizing institution in Roman imperial history. This was not a design intention. Augustus established the Guard as a personal security force — a professional bodyguard organized on military lines and stationed near Rome — because the emperor needed reliable protection and the Republic’s tradition of civilian governance had made no provision for one. What Augustus created as a security measure, his successors inherited as a power center whose loyalty could be purchased, whose commanders accumulated enormous influence, and whose physical proximity to the emperor gave it an influence over succession that no amount of constitutional theorizing could override.