The text gives no answer to this question. It can be deduced, however, that the demon and his legion would find great difficulty in possessing another victim outside of that region. It would appear that the God-given boundaries between nations and their regions (Acts 17:26) are acknowledged by the devil (see Matthew 4:8; Luke 4:5).
10 Et il le priait instamment de ne pas les envoyer hors du pays.