User blog comment:Darkcloud1111/Mistakes in The House of Hades/@comment-24308873-20131118230855/@comment-7492541-20131119001429

Calypso recognizing a standard Roman. She seems to know who are "Roman", although she was stuck on the island for thousands before Rome was founded.

Unless Hermes / Mercury did tries to take it from there, but forgotten because of the dual personality and Calypso was infected with personality change. XD  Calypso gentle = Greek form. Calypso rude= Roman form