Legend says that the town was founded by the hero of the Illiad, Diomedes; what we can be certain about is the presence of local Daunian settlements dating back to the Neolithic age (6000-3000 B.C.), and the metal Age. In the III century B.C. Canosa became one of the most important trading centres of Apulia.  An ally of Rome, it experienced considerable urban development due to its position along the via Traiana and the aqueduct, an amphitheatre, spa and rich mausoleums were built. In the IX century it was pillaged various times by the Saracens and flourished again in the Norman and Swabian periods. It began its final decline in the Imperial age, accelerated by numerous earthquakes and constant pillages.