Ethain was the king of Cidaris. The mage Dorregaray spied for him, and Dandelion sang at least once in his court. After the war with Nilfgaard, he was one of the negotiators of the peace treaty. Around the 1250s, a warlord had risen against him and King Foltest of Temeria, one of his allies, sent help.
- In the non-canon short story Something Ends, Something Begins, he is represented by Yves at Geralt and Yennefer's wedding.