Pisthetaerus
The driving force of the play. He starts as a disgruntled Athenian and ends as ruler of the universe. He is clever, persuasive, and increasingly ruthless. The play watches him transform from refugee to tyrant without ever quite condemning him.
Euelpides
Pisthetaerus's travel companion. He is warmer and funnier than Pisthetaerus but fades from the action once the city is established. He mostly serves as a sounding board in the first half.
Tereus (the Hoopoe)
A man transformed into a bird. He is the bridge between the human world and the bird world. He calls the bird assembly and helps Pisthetaerus get a hearing, but he is not a leader himself.
Iris
A messenger goddess who flies into Cloudcuckooland without permission. Her confrontation with Pisthetaerus shows how far his power has grown. She is sent back humiliated.
Heracles
One of the divine negotiators. He is easily distracted by food and ends up voting for whatever Pisthetaerus wants. His presence deflates any sense of divine dignity in the negotiation scene.
Sovereignty (Basileia)
A divine figure representing supreme power. She is offered to Pisthetaerus as a bride at the end, symbolizing his total takeover of cosmic authority. She has no speaking role but her presence closes the play's power transfer.