Stele describing gift of fields
Athens Epigraphical Museum, circa 285 BC
The Macedonians, a migratory pastoral people from the central and upper reaches of the Haliakmon River, having eliminated or absorbed the populations of Lower (present-day Central) Macedonia, who spoke other languages, introduced their own Greek dialect to the area.
Another strong presence in Macedonia since the late Mycenaean period had been that of the Ionic colonists; from early Classical times their presence had been strengthened under Athenian influence.
These contributing factors led to the appearance, in the 4th century BC, of a common tongue known as 'koine', based on the Attic speech. 'Koine' was adopted by Philip II as the official language of his kingdom, and was later disseminated to the confines of the Greek world by Alexander the Great.