Board Thread:Supergirl discussions/@comment-27700324-20180619050909/@comment-27700324-20180706212859

That isn't how being born in a certain country means. She would have to have been concieved there for that to be the case. However she was created on the outskirts of National City inside the new Fortress of Sanctuary. She then was materialized there in Siberia, but created in National City.

Story wise, this is Superman: Red Son being combined with Supergirl Vol. 5.