The Lives of the Twelve Caesars - La Vie des Douze Cesars

De vita Caesarum (Latin, literal translation: About the Life of the Caesars) commonly known as The Twelve Caesars, is a set of twelve biographies of Julius Caesar and the first 11 emperors of the Roman Empire written by Gaius Suetonius Tranquillus. The work, written in AD 121 during the reign of the emperor Hadrian, was the most popular work of Suetonius, at that time Hadrian's personal secretary, and is the largest among his surviving writings. The Twelve Caesars is considered very significant in antiquity and remains a primary source on Roman history. The book discusses the significant and critical period of the Principate from the end of the Republic to the reign of Domitian; comparisons are often made with Tacitus whose surviving works document a similar period.
Suetonius used the imperial archives to research eyewitness accounts, information, and other evidence to produce the book. The book can be described as racy, packed with gossip, dramatic and sometimes amusing.

Despite this, it provides valuable information on the heritage, personal habits, physical appearance, lives and political careers of the first Roman Emperors. It mentions details that other sources do not. For example, Suetonius is the main source on the life of Caligula, his uncle Claudius, and the heritage of Vespasian (the relevant sections of the Annals by his contemporary Tacitus being lost). Suetonius made a reference in this work to "Chrestus", which may refer to "Christ". During the book on Nero, Suetonius mentions a sect known as the Christians (see Historicity of Jesus). Like many of his contemporaries, Suetonius took omens seriously and carefully includes reports of omens portending Imperial births, accessions and deaths.