The Breve chronicon de rebus Siculis (of which both the publication and the first Italian translation is provided) is a particularly important source, full of valuable information on the history of southern Italy. It begins with brief essays by the Norman lords, and extends up to the end of the Swabian dynasty, sometimes offering extremely detailed descriptions. In particular, with regard to the life of Frederick II of Swabia, starting in June of 1228, the story even becomes like a diary, because the writer, who professes himself to be an eyewitness, provides a day-by-day account of the two-month period in which the emperor travelled from Brindisi to the Holy Land, where that bloodless crusade, with messianic tones, is said to have miraculously taken place. The text provides an excellent example of the typical compositional development of chronicle work. It consists of two main manuscripts, which contain extremely different texts at certain points. Not only are their final parts entirely discordant (one manuscript ends with the testament of Frederick II of 1250, while the other extends up until the battle of Benevento in 1266, therefore also including the death of Manfred and the conquest of the Kingdom by Charles of Anjou), but some of the information is also processed in an entirely conflicting manner, to the point that names and chronological events are irreversibly changed, albeit in a consistent manner. How should these differences be interpreted? Which of the two versions is most consistent with the «original»? And can one of them really be considered the «original»? This volume addresses these questions, by taking on the issue from a broader methodological standpoint.