In the wider context of the border conflicts that involve Rome as a third authority 'super partes', for which there is already evidence in the second century BC, two epigraphic documents stand out for the peculiarities distinguishing them from all others: the so-called Polcevera Tablet (concerning a dispute between Genuates and Viturii Langenses) and the Cippus Abellanus (related to a border dispute between Nolani and Abellani and written in Oscan). They make us aware of the political and municipal dynamics underlying the complex principle of Roman arbitration, often required to resolve territorial disputes, which were gradually evolving as Rome opened up to the East. What role did the Roman Senate play in such disputes? What exactly was the function of the referees sent by the City to settle the disputes with a super partes judgment? What was the importance of the agrarian reform of the Gracchi and the realisation of road axes in the acuity of such antagonisms? These are the questions which this study tries to an answer.