In Greek mythology, Achaeus or Achaios (/əˈkiːəs/; Ancient Greek: Ἀχαιός Akhaiós) was a son of Xuthus and Creusa, and the brother of Ion as well as the grandson of Hellen.^[1] According to Pausanias, he was the father of Archander and Architeles, who travelled from Phthiotis to Argos and each married daughters of Danaus.^[2]

The Achaeans regarded him as the author of their race, and derived from him their own name as well as that of Achaia, which was formerly called Aegialus. When his uncle Aeolus in Thessaly, whence he himself had come to Peloponnesus, died, he went there and made himself master of Phthiotis, which now also received from him the name of Achaia.^[3]

• Apollodorus, The Library with an English Translation by Sir James George Frazer, F.B.A., F.R.S. in 2 Volumes, Cambridge, MA, Harvard University Press; London, William Heinemann Ltd. 1921. ISBN 0-674-99135-4. Online version at the Perseus Digital Library. Greek text available from the same website.
• Brill’s New Pauly: Encyclopaedia of the Ancient World. Antiquity, Volume 1, A-Ari, editors: Hubert Cancik, Helmuth Schneider, Brill, 2002. ISBN 978-90-04-12258-1. Online version at Brill.
• Grimal, Pierre, The Dictionary of Classical Mythology, Wiley-Blackwell, 1996. ISBN 978-0-631-20102-1. Internet Archive.
• Hard, Robin, The Routledge Handbook of Greek Mythology: Based on H.J. Rose's "Handbook of Greek Mythology", Psychology Press, 2004. ISBN 978-0-415-18636-0. Google Books.
• Most, G. W., Hesiod: The Shield, Catalogue of Women, Other Fragments, Loeb Classical Library No. 503, Cambridge, Massachusetts, Harvard University Press, 2007, 2018. ISBN 978-0-674-99721-9. Online version at Harvard University Press.
• Pausanias, Description of Greece with an English Translation by W.H.S. Jones, Litt.D., and H.A. Ormerod, M.A., in 4 Volumes. Cambridge, MA, Harvard University Press; London, William Heinemann Ltd. 1918. ISBN 0-674-99328-4. Online version at the Perseus Digital Library

 This article incorporates text from a publication now in the public domain: Smith, William, ed. (1870). "Achaeus (1)". Dictionary of Greek and Roman Biography and Mythology.