In Greek mythology, Dionysius the Elder was a mortal (different from Dionysus, the god). His courtier, Damocles, mentioned one night that, as a person of power and authority, Dionysius must be very content and happy. Dionysius invited Damocles to a banquet, which he enjoyed very much sitting at Dionysius' throne. Damocles looked up and saw a sword hanging by a single piece of horsehair directly above his head and he thereafter realized the precarious position rulers are in. The Sword of Damocles is an oft-used allusion to this myth.

Dionysius once condemned a man named Pythias to death. He allowed Pythias to leave to settle his affairs first, as long as Damon, Pythias' friend, agreed to stay as hostage. Damon did so. When Pythias returned as promised, Dionysius let them both go.