Histiaeotis is first mentioned by Herodotus, when.. in the time of Dorus the son of Hellen, (Dorians) were in the territory around Mounts Ossa and Olympus, known as Histiaeotis. Then they were evicted from Histiaeotis by the Cadmeans and settled on Mount Pindus... Histiaeotis was also the seat of the Perrhaebi (Eth. Περραιβός), a warlike and powerful tribe, who possessed in historical times several towns strongly situated upon the mountains. They are mentioned by Homer as taking part in the Trojan War, and were regarded as genuine Hellenes, being one of the Amphictyonic states. The part of Hestiaeotis inhabited by them was frequently called Perrhaebia, but it never formed a separate Thessalian province. The Perrhaebi are said at one time to have extended south of the Peneius as far as the Lake Boebeis, but to have been driven out of this district by the mythical race of the Lapithae. It is probable that at an early period the Perrhaebi occupied the whole of Hestiaeotis, but were subsequently driven out of the plain and confined to the mountains by the Thessalian conquerors from Thesprotia.