The Bylliones were an Illyrian tribe that lived near the Adriatic coast of southern Illyria (modern Albania), on the lower valley of the Vjosa river, in the hinterland of Apollonia.
[5] Through contact with their Greek neighbours, in Hellenistic times the Bylliones acquired a certain degree of Hellenization and bilingualism, especially in the urban centres of their koinon.
[16] There is not a certain geographic extension of the community of the Bylliones,[17] whose territorial and ethnic institution is documented to have existed since the 5th-4th century BC, as evidenced by epigraphic material from the oracle of Dodona.
[17][18] The territory of the Bylliones was composed by a whole network of fortifications constructed to protect them from nearby Apollonians in the west and Atintanians in the east.
Through contact with their Greek neighbours, in Hellenistic times the Bylliones acquired a certain degree of Hellenization and bilingualism, especially in the urban centres of their koinon.
[6][28][29][30][9] In the earliest inscriptions found in the territory of the Bylliones that date to the 3rd century BCE all the personal names of the administrative figures are Illyrian, being members of the indigenous community in a still initial phase of the acculturation process.
[31] Illyrian onomastics is still present in the administrative inscriptions of the 3rd-2nd centuries BC, but there is an interference of names from nearby Apollonians, which show the progress in the acculturation process of the indigenous population.
[32] The time duration that passed before Illyrian cities like Byllis were documented on a list of theorodokoi, which occurred around 220-189 BCE, clarifies that acculturation did take place in southern Illyria, however it indicates that the process was gradual.
[12] Archaeological explorations have not yet found a sanctuary or temple in the city of Byllis, however, a series of inscriptions show the adoption of the cults of Zeus, Hera, Dionysius and Artemis.
[36] In the sanctuary of Dodona a 4th-century BC inscription on a lead foil reports Bylliones asking to which deity they should sacrifice in order to ensure the safety of their possessions.
All the personal names of these figures are Illyrian and provide evidence for an administration made up of members of the indigenous community in a still initial phase of the acculturation process.
[31] The prytanis, a magistrate figure, was adopted from nearby Apollonia originally introduced in the region under the influence of its metropolis Corinth, and it appeared as an eponymous official in several inscriptions found in the territory of the Bylliones.