We all know from the Bible about Augustus and Tiberius ruling at the time of Jesus Christ. We are also familiar with Caligula and Claudius and Nero. But what about the philosopher Marcus Aurelius musing in his favourite villa on the Danube in Austria? How about the wretched Valerian, used as a mounting block for the King of Persia before being flayed alive? Or Thrax, the seven-foot giant? Or Elegalabus, the sun-worshipping transgender Emperor?He who took the poisoned chalice of the Imperial purple was feared and respected.