The German terms Cäsarenwahn and Cäsarenwahnsinn gained some currency in the second half of the 19th century thanks to a novel by Gustav Freytag, a psychiatric treatise by Friedrich Wiedermeister, and a historical study by Ludwig Quidde. In the last two works, “Caesarian delusion” or “Caesars’ madness” mostly referred to Caligula’s alleged escapades (37-42 AD).
Of the burning of the Capitol (the temple of Jupiter Optimus Maximus) during the civil war in 69, Tacitus wrote that the ancient shrine had been destroyed by the “mad fury of emperors” (furore principum excindi). It was the Year of the Four Emperors, and the temple burned down in a conflict between Vespasian and Vitellius, both purple-wearers, which distinguished the standoff from a mere civil war, according to Tacitus.
More interesting – to me, at this moment – is Theodor Mommsen’s use of a similar term, Fürstenwahnsinn. Mommsen’s History of Rome did not go beyond Julius Caesar’s rule, but he studied the early emperors and lectured on that period (the posthumous “fourth volume” was compiled in the 1980s from his students’ notes). Mommsen didn’t think much of most emperors’ statesmanship:
In the long succession of these rulers, in the first three hundred years, out of the great number of insignificant, worthless, fatuous individuals there is not a single truly outstanding statesman; the most prominent among all of them, Tiberius ended his days in embittered princely madness; the best among the others were capable administrators, like Vespasian, or bellicose, second-rate army officers, like Trajan.
Although critical of the canonical trio of Roman historians, Mommsen apparently accepted that Tiberius’s later years were truly a reign of terror inspired by his imperial paranoia. One didn’t have to believe Suetonius’s scabrous fables to agree that Tiberius showed signs of mental disorder in his decade on Capri – the last ten years of his 77-year life (42 BC-37 AD) and his 22-year principate (14-37 AD).
Drawing historical parallels is cheap but what can you do if princely insanity keeps recurring?