This line of emperors ruled the Roman Empire, from its formation (under Augustus, in 27 BC) until the last of the line, Emperor Nero, committed suicide (in AD 68).[note 1]
The name Julio-Claudian is a historiographical term, deriving from the two families composing the imperial dynasty: the Julii Caesares and Claudii Nerones.
Nomenclature[edit]
Julius and Claudius were two Roman family names; in classical Latin, they came second. Roman family names were inherited from father to son, but a Roman aristocrat could—either during his life or in his will—adopt an heir if he lacked a natural son. In accordance with Roman naming conventions, the adopted son would replace his original family name with the name of his adopted family. A famous example of this custom is Julius Caesar's adoption of his great-nephew, Gaius Octavius.
Primogeniture is notably absent in the history of the Julio-Claudian dynasty. Augustus, Caligula and Nero failed to father biological and legitimate sons. Tiberius' own son, Drusus predeceased him. Only Claudius was outlived by his son, Britannicus, although he opted to promote his adopted son Nero as his successor to the throne. Adoption ultimately became a tool that most Julio-Claudian emperors utilized in order to promote their chosen heir to the front of the succession. Augustus—himself an adopted son of his great-uncle, the Roman dictator Julius Caesar—adopted his stepson Tiberius as his son and heir. Tiberius was, in turn, required to adopt his nephew Germanicus, the father of Caligula and brother of Claudius. Caligula adopted his cousin Tiberius Gemellus (grandson of the emperor Tiberius) shortly before executing him. Claudius adopted his great-nephew and stepson Nero, who, lacking a natural or adopted son of his own, ended the reign of the Julio-Claudian dynasty with his fall from power and subsequent suicide.
Augustus (Imperator Caesar Divi Filius Augustus), as Caesar's adopted son and heir, discarded the family name of his natural father and initially renamed himself "Gaius Julius Caesar" after his adoptive father. It was also customary for the adopted son to acknowledge his original family by adding an extra name at the end of his new name. As such, Augustus' adopted name would have been "Gaius Julius Caesar Octavianus". However, there is no evidence that he ever used the name Octavianus.[3][4]
Following Augustus' ascension as the first emperor of the Roman Empire in 27 BC, his family became a de facto royal house, known in historiography as the "Julio-Claudian dynasty". For various reasons, the Julio-Claudians followed in the example of Julius Caesar and Augustus by utilizing adoption as a tool for dynastic succession. The next four emperors were closely related through a combination of blood relation, marriage and adoption.
Tiberius (Tiberius Caesar Divi Augusti Filius Augustus), a Claudian by birth, became Augustus' stepson after the latter's marriage to Livia, who divorced Tiberius' natural father in the process. Tiberius' connection to the Julian side of the Imperial family grew closer when he married Augustus' only daughter, Julia the Elder. He ultimately succeeded Augustus as emperor in AD 14 after becoming his stepfather's adopted son and heir.[5]
Caligula (Gaius Julius Caesar Augustus Germanicus) was born into the Julian and Claudian branches of the Imperial family, thereby making him the first actual "Julio-Claudian" emperor. His father, Germanicus, was the son of Nero Claudius Drusus and Antonia Minor, the son of Livia and the daughter of Octavia Minor respectively. Germanicus was also a great-nephew of Augustus on his mother's side and nephew of Tiberius on his father's side. His wife, Agrippina the Elder, was a granddaughter of Augustus. Through Agrippina, Germanicus' children—including Caligula—were Augustus' great-grandchildren. When Augustus adopted Tiberius, the latter was required to adopt his brother's eldest son as well, thus allowing Germanicus' side of the Imperial family to inherit the Julius nomen.
Claudius (Tiberius Claudius Caesar Augustus Germanicus), the younger brother of Germanicus, was a Claudian on the side of his father, Nero Claudius Drusus, younger brother of Tiberius. However, he was also related to the Julian branch of the Imperial family through his mother, Antonia Minor. As a son of Antonia, Claudius was a great-nephew of Augustus. Moreover, he was also Augustus' step-grandson due to the fact that his father was a stepson of Augustus. Unlike Tiberius and Germanicus, both of whom were born as Claudians and became adopted Julians, Claudius was not adopted into the Julian family. Upon becoming emperor, however, he added the Julian-affiliated cognomen Caesar to his full name.
Nero (Nero Claudius Caesar Augustus Germanicus) was a great-great-grandson of Augustus and Livia through his mother, Agrippina the Younger. The younger Agrippina was a daughter of Germanicus and Agrippina the Elder, as well as Caligula's sister. Through his mother, Nero was related by blood to the Julian and Claudian branches of the Imperial family. However, he was born into the Domitii Ahenobarbi on his father's side. Nero became a Claudian in name as a result of Agrippina's marriage to her uncle, Claudius, who ultimately adopted her son as his own. He succeeded Claudius in AD 54, becoming the last direct descendant of Augustus to rule the Roman Empire. Within a year of Nero's suicide in AD 68, the Julio-Claudian dynasty was succeeded by the Flavian emperors following a brief civil war over the vacant Imperial throne.
The great-uncle/great-nephew blood relationship and/or adopted son relationship was commonly found among the rulers of the Julio-Claudian dynasty.
The other recurring relationship between emperor and successor is that of stepfather/stepson, a relationship not by blood but by marriage:
The uncle/nephew relationship is also prominent:
There were several instances of Emperors being father-in-law and son-in-law to each other:
The following bullet points illustrate the lineage of Julio-Claudian emperors (adoptions included; emperors in bold):
No Julio-Claudian emperor was a blood descendant of his immediate predecessor. Although Tiberius and Claudius had potential heirs (Tiberius Gemellus, grandson of Tiberius through his son Drusus, and Britannicus, son of Claudius, respectively) available for the succession, both were, in turn, ultimately succeeded by their great-nephews Caligula and Nero, respectively.
The fact that ordinary father-son (or grandfather-grandson) succession did not occur has contributed to the image of the Julio-Claudian court presented in Robert Graves's I, Claudius as a dangerous world where scheming family members were all too ready to murder the direct heirs so as to bring themselves, their own immediate families, or their lovers closer to the succession.