In Greek mythology, Arcas was a hunter who became king of Arcadia, the eponymous ancestor of the Arcadians. The son of Zeus and the nymph Callisto, he was remembered for teaching his people the arts of weaving, baking bread, and agriculture. After nearly killing his bear-transformed mother while hunting, he was set among the stars by Zeus, becoming the constellation Boötes (the Bear-warden) beside Callisto as Ursa Major.
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I.Family
Arcas was most commonly named as the son of Zeus and Callisto. Alternative accounts give his mother as Megisto, daughter of Ceteus (a descendant of Lycaon), or as Themisto, daughter of Inachus.
His wife varied considerably across the ancient sources. She is named as Laodamia or Leaneira, daughter of Amyclas of Sparta; as Meganeira, daughter of Crocon; as the nymph Chrysopeleia; or as the Dryad Erato.
His children likewise differ by source. His sons included Azan, Apheidas, Elatus, Triphylus, Erymanthus, and Pelasgus, along with an illegitimate son, Autolaus. His daughters were named as Hyperippe and Diomeneia. Apollodorus and Pausanias preserve differing versions of this genealogy.
II.Birth and protection
Callisto was a nymph in the retinue of the goddess Artemis, or in some sources a daughter of King Lycaon. Because she would be with no one but Artemis, Zeus disguised himself as the goddess and forced himself upon Callisto; the child of their union was Arcas.
Angered by the affair, Hera transformed Callisto into a bear. Zeus then hid the infant Arcas in a region of Greece that would come to bear his name, Arcadia, and entrusted his upbringing to Maia, one of the Pleiades.
III.Lycaon's feast
In one strand of the tradition, Arcas was caught up in the impiety of Lycaon. During a feast held by the king, the boy was placed upon a burning altar as a sacrifice to the gods.
Zeus intervened, restored Arcas whole, and turned his wrath upon the host: he transformed Lycaon into the first werewolf.
IV.King of Arcadia
Arcas grew to become king of Arcadia and the country's greatest hunter. He gave his name to the land and its people, who were called Arcadians after him.
He was credited with teaching his people the civilizing arts, including agriculture, the baking of bread, and the weaving of cloth, spreading these skills throughout Arcadia.
V.Catasterism
While hunting in the woods, Arcas came upon his mother in her bear form. Not recognizing her, he nearly killed her with an arrow.
Watching over them, Zeus stopped Arcas before he could shoot Callisto and raised them both into the heavens as constellations: Arcas as Boötes and Callisto as Ursa Major. Still angered, Hera petitioned Tethys to keep the two constellations perpetually above the horizon, denying them rest beneath the sea.
VI.Cult
Arcas received cult honors in Arcadia after his death. According to the instructions of the Delphic Oracle, his bones were brought from Mount Maenalus to an altar of Hera at Mantinea.