The family was traditionally held to have begun with Attius Clausus, a Sabine who favored peace with Rome . This was an unpopular position that led to him leaving Regillus with his followers around 504 BC. Rome was welcoming however, making his followers citizens and giving them land, and making Appius Claudius Sabinus Inregillensis, as he was called in Latin, a senator. It is assumed that the name came from the Latin claudeo (to limp), as many of the family members were lame, probably from some congenital disorder.
The following branches were descended from the censor Appius Claudius Caecus.
There were several major branches of the Claudian gens at the end of the Republic.
Note: Consuls of 51 and 49 BC were brothers and first cousins to the consul of 50 BC.
Note: Claudians after the death of Nero were most likely descended from freedmen of the Claudians, or men granted citizenship by Claudians.