The Julio-Claudian dynasty normally refers to the first five Roman Emperors: Augustus, Tiberius, Caligula (Gaius), Claudius, and Nero or the family to which they belonged; they ruled the Roman Empire from its formation, in the second half of the first century BC, until AD 68, when the last of the line, Nero, committed suicide.

None of the Julio-Claudians were succeeded by their sons; only one of them had a legitimate son survive him. The ancient historical writers, chiefly Suetonius and Tacitus, write from the point of view of the Roman senatorial aristocracy, and portray the Emperors in generally negative terms, whether from preference for the Roman Republic or love of a good scandalous story.