Tiberius Claudius Caesar Augustus Germanicus (1 August 10 BC – 13 October AD 54), born Tiberius Claudius Drusus, then Tiberius Claudius Nero Germanicus until his accession, was Roman Emperor from 41 to 54. A member of the Julio-Claudian dynasty, he succeeded his nephew Caligula. The son of Drusus and Antonia Minor, he was born in Lugdunum in Gaul, and was the first emperor to be born outside Italy. He was reportedly afflicted with some type of disability, and his family had virtually excluded him from public office until his consulship with his nephew Caligula in AD 37. Claudius' infirmity may have saved him from the fate of many other Roman nobles during the purges of Tiberius' and Caligula's reigns; potential enemies did not see him as a serious threat to them. His very survival led to his being declared emperor by Praetorian Guard after Caligula's assassination, at which point he was the last adult male of his family.

Despite his lack of political experience, Claudius proved an able administrator and a great builder of public works. During his reign, the empire conquered Britain, Thrace, Noricum, Pamphylia, Lycia, and Judea. He took a personal interest in the law, presided at public trials, and issued up to twenty edicts a day. However, he was seen as vulnerable throughout his reign, particularly by the nobility. Claudius was constantly forced to shore up his position; this resulted in the deaths of many senators. Claudius also suffered setbacks in his personal life, one of which may have led to his possible murder. These events damaged his reputation among the ancient writers, though more recent historians have revised this opinion. After his death in 54, his grand-nephew and adopted son Nero succeeded him as emperor.