The essay retraces the public debate about the 1975 Osimo Treaty. The pact settled the dispute with Yugoslavia over the Italian eastern boundary. It was portrayed by the Italian center-left government as a great diplomatic achievement and as the fi nal act of the Italian-Yugoslavian appeasement (reconciliation) negotiations through a successful management of Aldo Moro’s «Ostpolitik », fostered by the Democrazia cristiana (DC) party. The treaty provoked however not only harsh tensions within broad sectors of Trieste’s citizenry but also disunity within the local DC party itself. The study examines the stances taken in the Italian parliamentary sessions and in the national press. Furthermore, it focuses on the Trieste’s political debate. Referring to this latter setting, the local community witnessed the emergence of a varied and widespread opposition against certain political, national, economic and environmental provisions of the treaty. The re-emergence of unrelieved political quarrels and myths – including both municipal and national issues – testifi ed the inability of the DC party in convincing a large part of the local public opinion to accept the guidelines for normalization of the city within the wider national strategy of normalization in the Adriatic area. Thus, the Osimo Treaty marked the end of the predominance of the DC in the local political scenery: the party was quickly supplanted by the Lista per Trieste movement.
