Tiberius

Born in 42 BC to a politician and Livia Drusilla, Tiberius became Augustus's stepson when his mother divorced and remarried. He built his reputation as a general and diplomat, conquering Pannonia, Dalmatia, Raetia, and parts of Germania to secure Rome's northern frontier. Augustus forced him to divorce his beloved wife Vipsania and marry the emperor's daughter Julia - a scandalous, childless disaster that ended in her exile - then made him adopt the popular Germanicus as heir, sidelining Tiberius's own son. He became emperor in AD 14 at fifty-five, reluctant and visibly inadequate to the shadow he filled. Efficient but paranoid, he clashed with the Senate, grew reclusive after Germanicus and his son Drusus both died, and in 26 left Rome entirely, governing through his praetorian prefect Sejanus until he had him executed for treason. He died in 37, leaving behind full coffers, no divine honours, and Pliny the Elder's verdict: "the gloomiest of men."