As long as the Romans had contact with the people of Italy only, their treaties embodied the concept of societas. The new formula "amicitia and societas" and the expression amicitia seem to have arisen only when Rome came into contact with other peoples in the Mediterranean area. The article aims to demonstrate that the roots of these new relationships are in international relations in the ancient Near East, and that the Romans adopted them from the Greeks. Later, they adapted the formula to their policy of expansion by using it to impose the maiestas populi Romani.