Pieres

The Pieres (Ancient Greek,"Πίερες") were a Thracian tribe^[1] connected with the Brygi,^[2] that long before the archaic period in Greece occupied the narrow strip of plain land, or low hill, between the mouths of the Peneius and the Haliacmon^[3] rivers, at the foot of the great woody steeps of Mount Olympus.^[4] This region was named after them as Pieria (Greek: Πιερία).

^ Orpheus and Greek Religion (Mythos Books) by William Keith Guthrie and L. Alderlink, 1993, page 62: "... assigned, Pieria, was originally inhabited by a Thracian tribe, the Pieres, who according to Thucydides (ii. ..."
^ W. W. How, J. Wells, A Commentary on Herodotus,6.45 ,"Βρύγοι. These Thracian neighbours of Macedon may be placed between the Strymon and Mount Athos. In the list of tribes given in vii. 185 they come between the men of Chalcidice and the Pieres. The two passages agree if in vii. 185 the Pieres are the branch of the tribe who lived east of the Strymon (vii. 112). Scymnus Chius (434) and Strabo (326) locate the Brygi far to the west on the borders of Epirus and Illyria. Probably they are connected with the Βρίγες (vii. 73), the European ancestors of the Phrygians."
^ E.C. Marchant, Commentary on Thucydides: Book 2,Στενήν—the Paeonians had possessed ‘a narrow strip on the bank of the Axius, down to Pella and the sea.’ Grote points out that this would leave hardly any room for the Bottiaeans, who dwelt north of the Pierians, between the mouth of the Haliacmon (the Indjeh Kara-su) and that of the Axius. Probably Thuc. is mistaken in saying μέχρι θαλάσσης, and the Paeonians did not extend so far east
^ Strab. 7.7,"As for the Thracians, the Pieres inhabited Pieria and the region about Olympus"