Il cognomen Regillensis e la tradizione sulla battaglia del lago Regillo

The Regillensis cognomen, attested by the Triumphal Capitoline Fasti for Aulus Postumius, the dictator who won over the Latins at Regillus’ lake in 499 or 496 BC, has been interpreted by a part of the modern historiography as a cognomen ex virtute. This however contradicts Livy’s statement (30.45.7), according to which Scipio Africanus was the first Roman general honoured with this type of title. For this reason, this work aims to shed light on the original meaning of the Regillensis cognomen and on its reinterpretation during the following centuries: born as a cognomen ex origine for some members of the gens Postumia living in Rome between the end of the 5th and the first half of the 4th century BC, then extinct, the title was reinterpreted as a cognomen ex virtute and first traced back to Aulus Postumius in a much later period, when the tradition of the cognomina ex virtute was already widespread and well-known; this probably happened at the same time of the writing of the Capitoline Fasti in the Augustan age. The evolution of the cognomen is also strictly related to the formation of the legend on the battle of the Regillus’ lake: we outline here the different stages of the historiographical elaboration.