Born the emperor’s son, in the year of his father’s accession
Tiberius Claudius Caesar Britannicus was born to Claudius and Messalina within weeks of his father’s unexpected accession in 41 CE; his name commemorated the ongoing conquest of Britain. As Claudius’s only surviving son, he held, for a time, the clearest biological claim to succeed his father of anyone in the family.
Outranked by an adopted rival
Messalina’s execution in 48 CE and Claudius’s subsequent marriage to Agrippina the Younger changed Britannicus’s position permanently. Agrippina secured the adoption of her own son, the future Nero, in 50 CE; Nero was several years older, received precedence in public honours, and married Britannicus’s sister, Claudia Octavia, tying the two boys together while placing Nero ahead in line.
Death on the eve of adulthood
Claudius died in 54 CE and Nero succeeded him. Tacitus reports that Britannicus died suddenly at a banquet in February 55 CE, poisoned on Nero’s order, just days before his fourteenth birthday would have marked his formal coming of age. His death removed the one rival with a stronger biological claim to the throne than Nero himself.
Historical sources
Tacitus, Annals 12.25–26; 13.14–17
Britannicus’s displacement by Nero’s adoption and the circumstances of his death.
Suetonius, Nero 33
Nero’s responsibility for Britannicus’s poisoning.
Portrait: Marie-Lan Nguyen / Wikimedia Commons. Public domain. Cropped and resized for display.