1248, la battaglia che cambiò data: manipolazione cronologica e comunicazione imperiale in alcune lettere della cancelleria di Federico II

The letters of Frederick II of Swabia represent a source of great importance for reconstructing the emperor’s ideology and government practice, but their use requires great caution. The paper examines the case of a naval battle fought at the beginning of 1248 on the Po River and won by the emperor’s son, Enzo, proposing the hypothesis that the imperial notaries deliberately modified the chronology of the battle, moving it from the beginning to the end of February, in order to spread the news of a presumed imperial revenge, after the defeat suffered by Fredrick II at Vittoria (Parma) on February 18.