Chaonians

The Chaonians (Greek: , "Cháones") were an ancient Greek tribe that inhabited the region of Epirus located in the north-west of modern Greece and southern Albania. Together with the Molossians and the Thesprotians, they formed the main tribes of the northwestern Greek group. On their southern frontier lay another Epirote kingdom, that of the Molossians, to their southwest stood the kingdom of the Thesprotians, and to their north lived the Illyrian tribes. According to Virgil, Chaon was the eponymous ancestor of the Chaonians. By the 5th century BC, they had conquered and combined to a large degree with the neighboring Thesprotians and Molossians. The Chaonians were part of the Epirote League until 170 BC when their territory was annexed by the Roman Republic.
History.
According to Strabo, the Chaonians (along with the Molossians) were the most famous among the fourteen tribes of Epirus, because they once ruled over the whole of Epirus. The Periplus of Pseudo-Scylax makes a clear distinction between the Chaonians and their northern neighbours, the Illyrian tribes that occupied the coastal and hinterland regions further north. Epirotic tribes whether Chaonian or Molossian inhabited the plain of Korce and the valley of the Erigon.
Some of the tribes that belonged to the Chaonians had practised tumulus burial during or at the end of the Bronze Age. This featured continued to the Iron Age. After c. 650 B.C their rule extended to the southern part of the lakeland (Prespa-Ohrid), while the Dassaretai were their northernmost tribe. During this period the Chaonians were the most powerful tribal state in Epirus. They were later succeeded by the Molossians. Though they lost some pastures at that time they managed to retain control of an area stretching from Grammos mountain (ancient Boion) to the southwest of Ohrid-Prespa lakes. They also lost some regions in their north, in particular the southern part of Malakastra plain to the Greek colony of Apollonia as well as to the Taulantians. 
The Illyrians and Chaonians appear to have had – at least at times – a confrontational relationship; Polybius recounts a devastating raid mounted in 230 BC by the Illyrians against Phoenice, the chief city of the Chaonians. The incident had major political ramifications where many Italian traders who were in the town at the time of the sacking were killed or enslaved by the Illyrians, prompting the Roman Republic to launch the first of the two Illyrian Wars the following year.
Political structure.
The Chaonians were settled "Kata Komas" () meaning in a collection of villages and not in an organized "polis" (despite the fact that they called their community a "polis") and were a tribal state in the 5th century BC. Aristophanes had used the name of the tribe as a pun to illustrate the chaos of Athenian foreign policy. According to Thucydides, their leaders were chosen on an annual basis; he names two such leaders, Photius and Nikanor "from the ruling lineage". In the 4th century BC, the Chaonians adopted the term "prostates" (Greek: προστάτης, "ruler") to describe their leaders, like most Greek tribal states at the time. Other terms for office were "grammateus" (Greek: Γραμματεύς, "secretary"), "demiourgoi" (Greek: δημιουργοί, "creators"), "hieromnemones" (Greek: ἱερομνήμονες, "of the sacred memory") and "synarchontes" (Greek: συνάρχοντες, "co-rulers"). 
They were loosely associated with the rest of the Epirote tribes ( "phylae"), including the Thesprotians and Molossians. They joined the Epirote League, founded in 325/320 BC, uniting their territories with those of the rest of the Epirotes in a loosely federated state that became a major power in the region until it was conquered by Rome in 170 BC. During the 2nd century, the Prasaebi replaced the Chaones in their control of Buthrotum, as attested in inscriptions from that period.
The religious centre of all Epirote tribes was in Dodona, which was also one of the main oracles of the Greek world.
Geography.
Chaonia or Chaon (Ancient Greek: Χαονία or Χάων) was the name of the northwestern part of Epirus. Strabo in his "Geography" places Chaonia between the Ceraunian Mountains in the north and the River Thyamis in the south.
Phoenice (Phoinike) was the capital and most important city of the Chaonians. The strength of the Chaonian tribes prevented the Greek city-states from establishing any colonies on the coast of Chaonia.
Language.
Due to the fact that Greek toponyms that preserve archaic features are very densely found in the wider area, it appears that speakers of the proto-Greek language inhabited a region which included Chaonia before the late Bronze Age migrations (late 3rd-early 2nd millennium B.C) during several centuries or even millennia before. There is today an overall consensus that the Chaonians were among the Greek-speaking population of Epirus, which spoke the North-West Doric dialect of Ancient Greek, akin to that of Aetolia, Phocis, and certain other regions, this is also attested by the available epigraphic evidence in Epirus. Eugene Borza argues that the Molossians originated from those Proto-Greek tribes that inhabited northwestern Greece in c. 2.600 BC. Hammond argues the Chaonians and other Epirote tribes spoke Greek at least from the Dark Ages (1100–800 BC). Pseudo-Scylax' description of the Greek World of c. 380-360 B.C indicates that they didn't speak Illyrian, while Hammond argued that their acceptance in 330 B.C of the Epirote League indicates that they spoke Greek. Chaonian inscriptions (all in Greek) began around 329 B.C.E. 
Thucidydes describes them as "barbaroi", while the "ruling family" ("τό άρχικόν γένος") apparently had Greek names. Crossland argues that Thucydides' writings indicate that during his lifetime, the tribes from Amphilochia northward were not Greek-speaking, though already under strong Greek influence, and they would later adopt the Greek language in the fourth century. On the other hand, Hammond argues that they spoke Greek during and before the time of Thucydides considering that Greek language and Greek names of their inscriptions were not suddenly adopted. As for the identity of the language they spoke before Greek, it may have been neither Greek nor Illyrian.
Filos argues that there were some local peculiarities among the Greek speaking tribes of Epirus. Additionally, in the northern part of the region of Epirus, contact with Illyrian increased sub-dialectal variation within North-West Doric, although he admits that concrete evidence outside of onomastics is lacking. On the other hand penetration of Greek speech, including Epirote, was much more evident among the adjacent Illyrian tribes.
Mythological origins.
The Chaonians claimed that their royal house was of Trojan descent, asserting ancestry through the eponymous hero Chaon (Ancient Greek: Χάων) who gave his name to Chaonia. The stories are unclear as to whether he was the friend or the brother of Helenus, the son of Priam of Troy, but in either case, he accompanied him to the court of Neoptolemus, the son of Achilles who was credited with founding the city of Buthrotum. The stories concerning Chaon's death are as unclear as that of his relationship to Helenus. Chaon was either killed in a hunting accident or offered himself as a sacrifice to the gods during an epidemic, thus saving the lives of his countrymen. In either case, when Helenus became the ruler of the country, he named a part of the kingdom after Chaon. The Chaonians' neighbours, the Molossians and Thesprotians, also asserted Trojan ancestry. It has been suggested that the very similar Chaonian origin-myth may have arisen as a response to the self-definitions of the Molossians and Thesprotians.