The Furies

The Erinyes are older than the Olympians. Hesiod has them born from the blood of Ouranos when he was maimed by his son — which makes them, from the first moment, the consequence of a crime against a father. Their names are Alecto the unceasing, Megaera the grudging, and Tisiphone the avenger of murder.

They pursue a specific class of offence: perjury, violation of the guest-host bond, and above all the killing of blood relatives. They do not judge and they do not stop. In Aeschylus they are described as black-robed with snakes in their hair, and they hound Orestes across the Greek world for killing his mother, even though a god told him to do it.

That case is the turning point. Athena convenes the first murder trial in Athens, the vote ties, and she casts for acquittal — and then has to deal with the Furies, who are furious that a court has overruled vengeance. Her solution is not to defeat them. She offers them a place of honour beneath the city as the Eumenides, the Kindly Ones, and they accept.

That euphemism is the most revealing thing about them. Greeks avoided saying their real name aloud, in case it drew their attention. Calling them 'the Kindly Ones' was not affection; it was insurance.