“"The language spoken by these early Macedonians has become a controversial issue in modern times. It seems not to have been so in antiquity. As we have seen, Hesiod made Magnes and Macedon first cousins of the Hellenes, and he therefore regarded them as speakers of a dialect (or dialects) of the Greek language. That he was correct in the case of the Magnetes has been proved by the discovery of early inscriptions in an Aeolic dialect in their area of eastern Thessaly. Then, late in the fifth century a Greek historian, Hellanicus, who visited the court of Macedonia, made the father of Macedon not Zeus but Aeolus, a thing which he could not have done unless he knew that the Macedonians were speaking an Aeolic dialect of Greek. A remarkable confirmation of their Greek speech comes from the Persians, who occupied Macedonia as part of their conquests in Europe c.510-480. […] Disagreements over this issue have developed for various reasons. In the second half of the fifth century Thucydides regarded the semi-nomadic, armed northerners of Epirus and western Macedonia as "barbarians", and he called them such in his history of events in 429 and 423. The word was understood by some scholars to mean "non-Greek-speakers" rather than "savages." They were shown to be mistaken in 1956, when inscriptions of 370-68, containing lists of Greek personal names and recording in the Greek language some acts of the Molossians, were found at Dodona in Epirus. This discovery proved beyond dispute that one of Thucydides "barbarian" tribes" of Epirus, the Molossians, was speaking Greek at the time of which he was writing. Demosthenes too called the Macedonians "barbarians" in the 340s. That this was merely a term of abuse has been proved recently by the discovery at Aegae (Vergina) of seventy-four Greek names and one Thracian name on funerary headstones inscribed in Greek letters.”

"The Miracle That Was Macedonia", Palgrave Macmillan (September 1991)