The present dissertation provides a historical ethnomusicological study on the liturgical chant tradition of the Arbëreshe communities in Sicily based on oral and written sources. The musical repertoire has been cultivated by priests and faithful adhering to the Byzantine rite since the time of the Albanian diaspora in Italy in the aftermath of the Fall of Constantinople. As a matter of fact, the repertoire seems to be maintained through a delicate balance between techniques of ‘reception’, ‘safeguarding’, and ‘re-byzantinisation’ that characterize both its present oral chant administration and its historical development, and function as marker of identity among the Arbëreshe community in Sicily. Therefore, the Byzantine chant heritage in Sicily is not an inflexible and static musical tradition, but it envisages a dynamic mode of existence, susceptible to changes, and maintained by interior principles of organisation. After five centuries of oral transmission, it still lives, despite, or maybe thanks to the lack of ‘original’ written sources, and it might thus be seen as a multi-layered musical tradition, featuring multiple versions and encompassing a certain degree of melodic heterogeneity.