The first navigation around the world, between 1519 and 1522, led by Fernand Magellan and achieved under the command of Sebastiano Elcano, gave rise to many accounts. The two oldest ones are the letters written in Latin by two clerks of Charles V, Pietro Martire d’Anghiera (1457-1526) and Maximilianus Transylvanus (ca. 1485-1538), who collected and wrote down the oral testimonies of the survivors of the expedition in Valladolid and sent them to their correspondents, in Germany and Italy starting in 1523. The importance of these two letters resides not only in the quality of the reported facts, but also in the point of view of these courtiers that had connections with humanists from all over Europe. The article analyzes how these authors contributed to inventing the modern discourse on “great discoveries”, by presenting the exploit of Magellan and his sailors as a scientific progress surpassing the knowledge inherited from Antiquity; it shows how these two letters also contain the seeds of a moral critique of European societies and of the utopian search for better worlds.