Paul Diacono writes that to the times of duke Romoaldo's of Benevento, a colony of Bulgarian, driven by one prince of theirs, Alzeco, came (680) in the dukedom of Benevento and pacifically asked for to be able to be appropriated in the territory.

Duke Romoaldo allowed that they installed themselves in the desert places around Cepino, Isernia and Boviano. Prince assumed the title of gastaldo, of officer of the duke. There is news that still in the VIII century they preserved their nationality speaking their language over the Latin.

Recent searches have the tendency to show that the duke Romoaldo had allowed that part of the colony was in the zone of Paestum then redoubt to alone reserve of hunting (ad capiendias aves) and that there were pushed over the Alento appropriating themselves to the strata of a mountain that from them took the name (Bulgheria Mountain).Goffredo Malatesta remembers that Roberto the Guiscardo had recruited Slavics of Celle (of Bulgheria) because they knew all the footsteps of the territory.

Rather Antonini writes to have read of some concessions served as Roberto in 1080 to the Bulgarian, or slaves, of the place for services made him «in finibus Apuliae et Salerni », attributing the immigration of the Bulgarian to Alboino, which « oltre ai suoi Longobardi, and Sassoni, menovvi (in ltalia) ancora Bulgari».

Probably center of a «laura » with cells of italo-Greek monks, for which the name of Celle to the inhabited area risen around it; the village followed the fates of Roccagloriosa, of which it was hamlet up to his elevation to town center.

We have news however that the vassal of Centola, besides demanding the «bagliva » of Foria also demanded that of Poderia, fraction of Celle now.Village, the latter of which, to say dell'Antonini barons were Latino Tancredi, author of «de Naturae Miraculis» and Giovanni Andrea George, known for its Legal works.At the end of 1700, Celle belonged to d'Afflitto family from Roccagloriosa.