[1][2][3][4][5] According to the tradition of the Orestae, which is recorded by Theagenes and Strabo, their name was derived from Orestes, or a like-named son of his; though, the historical value of this myth is not acknowledged, and is considered improbable.
[12][13][14] Orestis bordered to the southwest Molossians and other Epirotic peoples, to the northwest Dassaretia, to the west Parauaia, to the northeast Eordaea and to the southeast Elimiotis.
Papazoglou adds that the mountains of Morava (between Korcë plain and Poloskë basin) and Grammos probably formed the border with Dassaretia and Parauaia.
[13][17] Some important cities in the Orestis region based on ancient sources were Argos Orestikon, Celetrum (Kelethron), Diokliteionopolis, while epigraphic evidence cofirms the existence of Battyna and Lykke.
[19] Orestis formed the western border of Upper Macedonia, and Illyrians beyond this district constituted a persistent menace to the stability of the Kingdom of Macedon.
[21] An abundance of Mycenaean findings (both imported and locally made) from the late Bronze Age have been unearthed from various tombs in the region of Orestis.
[22] Appian and Hesiod mention about the origins of the Argead dynasty of the Macedonian royal house that they were descendants of Argeas from Orestis, the later being son of the eponymous Macedon.
[30][31] An inscription from the upper Devoll valley, lists Artemis with the epithet Syvonnike, while depictions of the goddess are found in various parts of the Orestis region.