What it is
The Twelve Caesars (De vita Caesarum) is Suetonius's set of biographies of Julius Caesar and the first eleven emperors — Augustus, Tiberius, Caligula, Claudius, Nero, Galba, Otho, Vitellius, Vespasian, Titus and Domitian. Composed around 121 CE while Suetonius held a senior secretarial post under Hadrian (with access, for at least part of the work, to the imperial archives), it is the most important biographical source for the early Principate after Tacitus, and the most quoted.
Historical context
Suetonius wrote as a scholar and imperial functionary rather than as a senator-historian in the Tacitean mould. His training was antiquarian; his sources included documents, letters and physical records as well as the floating mass of court anecdote. The result is a work close to the imperial center in its materials and detached from senatorial moralising in its manner.
What it argues — by how it is organised
The Twelve Caesars makes its argument structurally. Suetonius does not narrate a reign chronologically; he organises each life per species, by category — ancestry, early career, public acts, then private character, appearance, habits, omens, death. This is biography as dossier rather than as story, and its effect is distinctive: by separating the public record from the private man, Suetonius implies that the truth of an emperor lies as much in his table manners, his sexual conduct and his superstitions as in his administration. The method is why the Twelve Caesars is the source for nearly every memorable image of the early emperors — Caesar's comb-over and his last words, Augustus's frugality, Caligula's horse, Nero and the fire, Vespasian's deathbed joke. Tacitus diagnoses the system; Suetonius collects the man.
Reception and influence
The work was a medieval favourite — Einhard modelled his Life of Charlemagne directly on Suetonius's Augustus — and it has governed the popular imagination of Rome ever since, from Renaissance painting to Robert Graves's I, Claudius and the screen. The platform reads it with care: its anecdotes are vivid, frequently hostile, and not always weighed for reliability. Used critically and against Tacitus and the documentary record, it is indispensable; used credulously, it is how myths about the Caesars are manufactured.
Citing the Twelve Caesars
Standard citation is by life and chapter (e.g. Aug. 28 for Augustus's claim to have found Rome brick and left it marble; Jul. for the life of Caesar). Edwards's edition is the standard scholarly English reference. See our Sources page.