On May 29, 1416, a Venetian fleet was attacked by a Turkish fleet off the harbour of Gallipoli, and decisively defeated it. The report that the Venetian commander, Piero Loredan, sent to the Senate is preserved in two very similar versions, in the contemporary chronicle of Antonio Morosini and in the later work De Origine Urbis Venetae et Vita Omnium Ducum written by Marin Sanudo. Sanudo’s version, however, omits one incident. The omission can be explained by the fact that the person concerned (Dolfin Venier) was distantly related to him. This shows that scholars need to examine every source for medieval history carefully, even if they sometimes seem to be recycling the same material.