Before she became a national treasure, with the TV shows and blogs, Mary Beard was already influential in keeping the ancient world alive in modern thinking. As classics editor of the Times Literary Supplement since 1992, she has ensured many books have been reviewed beyond the narrow confines of scholarly journals. Her own books, combining accessibility with profound knowledge lightly worn, have always had a wide readership. Among other themes, she has explored classical art, Pompeii and the subject of laughter in ancient Rome. Now she turns her attention to the role of the Roman emperor, from the rule of Augustus (31 BC–AD 14) to the death of Alexander Severus in AD 235.

In an engaging prologue, ‘Dinner with Elagabalus’ (Elagabalus was the teenage emperor said to have smothered his guests to death with flower petals), she states that she will be dealing with both ‘down-to-earth questions’ relating to the everyday lives of Roman rulers and more abstract ideas of how they were thought about, both by their subjects and by themselves (‘emperors of the imagination’ is the nice term she uses). First, though, she sets the scene by explaining how one-man rule was reintroduced to Rome. The Roman Republic (509–31 BC) was a victim of its own success. Institutions created for a small city-state were not suited to governing a Mediterranean-wide empire. Military commands covering wide swathes of territory, and lasting for years, brought their holders vast wealth and glory. The gap between the winners and the losers in the senatorial elite became too great. Ultimately, one man had to win.

The subject of succession opens the book proper. The first emperor, Augustus, set up an autocracy while claiming that he was going to restore the republic. Beard is always illuminating on the deceits at the heart of the emperors’ rule. In a series of ad hoc experiments aimed at