thumb|upright=0.8|[[Tiberius Caesar Augustus, second Roman emperor]]
The gens Claudia (), sometimes written Clodia, was one of the most prominent patrician houses of ancient Rome. The gens traced its origin to the earliest days of the Roman Republic. The first of the Claudii to obtain the consulship was Appius Claudius Sabinus Regillensis, in 495 BC, and from that time its members frequently held the highest offices of the state, both under the Republic and in imperial times.
Plebeian Claudii are found fairly early in Rome's history. Some may have been descended from members of the family who had passed over to the plebeians, while others were probably the descendants of freedmen of the gens.
The patrician Claudii were noted for their pride and arrogance, and intense hatred of the commonalty. In his History of Rome, Niebuhr writes,
<blockquote>That house during the course of centuries produced several very eminent, few great men; hardly a single noble-minded one. In all ages it distinguished itself alike by a spirit of haughty defiance, by disdain for the laws, and iron hardness of heart.</blockquote>
During the Republic, no patrician Claudius adopted a member of another gens; the emperor Claudius was the first who broke this custom, by adopting Lucius Domitius Ahenobarbus, afterwards the emperor Nero.
Origin
According to legend, the first of the Claudii was a Sabine, by the name of Attius Clausus, who came to Rome with his retainers in 504 BC, the sixth year of the Republic.