The coronation of Roger II of Altavilla in 1130 was the foundation act of the Kingdom of Sicily. The king then began to create the ideological foundations of his new royal authority. They seem to be reflected in the royal titulary as seen in the charters he issued. The initial period of the reign is particularly rich in terms of formulas used in royal diplomas: it seems that Roger II (or his chancery) was then looking for ways to define the foundations of the royal power in Sicily. Of particular note is the phrase christianorum adiutor et clipeus used by the king in the first years of his reign. There is also a particular devotional formula used almost exclusively by emperors at that time: divina favente clementia, as well as the title rex semper augustus. These terms may suggest that Roger II drew the ideological foundations of his power not only from Byzantine models but that he could have been inspired by the ideological patterns of the Western Empire.
The aim of the paper is to present the formation of the titulary of the kings of Sicily in the first years of Norman Sicilian monarchy. I believe it allows to understand the basis for Roger II’s legitimization of the royal power, and to some extent it also reflects and helps to understand the political reality in which the new kingdom was created.