The first imperial dynasty of the Roman Empire was the Julio-Claudian one, and the first five emperors of Rome belonged to this dynasty.
- Emperor Augustus (reigned 27 BC–AD 14)
- Emperor Tiberius (reigned 14–37 AD)
- Emperor Caligula (reigned 37–41 AD)
- Emperor Claudius (reigned 41–54 AD)
- Emperor Nero (reigned 54–68 AD)
This meant that the Julio-Claudian dynasty was in charge of the impire from its formation under Agustus in 27 BC to Nero’s suicide in 68 AD.
The Julio-Claudian dynasty is named after its two main branches of the imperial family; the patrician houses gens Julia and gens Claudia.
Lack of suitable heirs
Interestingly, there is a notable lack of sons in the Julio-Claudian dynasty, if we by son mean a male offspring that is both born within wedlock and is the genetical (not adopted) son of the legal father. Neither Augustus, Caligula or Nero fathered any such son. Tiberius had a natural and legitimate son named Drusus, but Drusus died age of 36, when his father was still alive.
Only Claudius had a natural and legitimate son that also outlived him. This was his son Britannicus, born to Claudius third wife Valeria Messalina in 41 AD. He did not succeed his father Claudius on the imperial throne however, since Claudius adopted his step-son (Lucius) Nero. Nero was Claudius fourth wife’s son from a previous marriage, and Nero’s mother used her clout to ensure he succeeded Claudius on the throne instead of (the still underage) Britannicus.
Because of this mesmerizing lack of natural and legitimate sons, the adoption of adult or almost adult males became important for the Julio-Claudian emperors. Agustus himself had been adopted by his great-uncle, Julius Caesar, and Agustus went on to adopt his stepson Tiberius and appoint him his heir.
When Tiberius natural and legitimate son Drusus died at the age of 36, Tiberius had not other legitimate heir. He remedied the situation by adopting his nephew Germanicus (the brother of Claudius and father of Caligula).
Caligula adopted his cousin Tiberius Gemellus, who was the grandson of Tiberius, but then had him executed shortly afterwards.
Claudius adopted Nero (Lucius), who wasn’t just his stephson but also his great-nephew.
When Nero fell from power and committed suicide, he left neither a natural and legitimate heir nor any adopted heir. This marked the end of the reign of the Julio-Claudian dynasty.