In Greek mythology, Icarius of Athens welcomed Dionysus, learned viticulture, and shared wine with shepherds who, thinking themselves poisoned, killed him. His daughter Erigone and the hound Maera found the body; Erigone hanged herself. Dionysus punished Athens until rites for father and daughter were established; they and Maera were placed among the stars. Distinct from Spartan Icarius (father of Penelope) and from Icarus of the wings.
Adapted from Wikipedia, "Icarius (Athenian)" · CC BY-SA 4.0
I.Gift of wine
When Dionysus came to Attica, Icarius received him hospitably. The god rewarded him with the vine and taught him to make wine. Icarius offered the drink to shepherds; intoxicated, they believed he had poisoned them and murdered him. Erigone, searching with the dog Maera, found the grave and hanged herself in grief.
Dionysus sent a plague of madness on Athens's unmarried women, who hanged themselves after Erigone's example. The scourge ended only when the Athenians instituted honorific rites for Icarius and Erigone. Zeus or Dionysus set Icarius in the sky as Boötes, Erigone as Virgo, and Maera as the star Procyon (or Canicula in related notices).
II.Homonyms
Atlas id icarius is the Spartan prince, brother of Tyndareus and father of Penelope. Id icarius-attica is the Athenian host of Dionysus. Neither is Icarus son of Daedalus, whose name is similar but whose myth is the Cretan flight.