A companion of Peisetairos, also from Athens, who hopes to escape city life and seeks ease and comfort rather than power. He plays a significant role in the early parts of the story but fades into the background as the plot advances.

A group of 24 dancers and singers representing different species of birds, initially fearing humans but eventually persuaded by Peisetairos’s vision. They support Peisetairos and help build Cloudcuckooland.

The leader of the birds, based on the mythical figure Tereus, who mediates between the birds and the human characters. He encourages the birds to consider Peisetairos’s plans but disappears after the city's foundation.

The messenger of the gods who briefly appears as Cloudcuckooland's walls are erected. She is surprised by Peisetairos’s rebellion against the gods and reports back about the new bird city.

An enemy of Zeus who comes stealthily to Cloudcuckooland to advise Peisetairos. He offers crucial guidance on how to deal with the gods, mirroring his mythological role as a helper to humanity.

One of the speaking members of the divine embassy negotiating with Cloudcuckooland, portrayed as a senior member overseeing others. He tries to maintain the gods' status but is challenged by the situation.

A member of the divine embassy known for his foolishness and gluttony, easily tempted by a feast during negotiations. He is swayed by Peisetairos’s manipulation to take the birds' side.