Realms are not immediately deleted when their last region is lost. Deletion is a manual process, and cn only be done by Tom. He likes to give the characters a while to find new realms, before the lost realm is deleted and the remaining nobles in it sent rogue.
Entai was a realm formed by the secession of the city of Aegir from Morek Empire. It was short lived, as all the nobles in it left and went to Astrum as soon as the Carwyn/Astrum war started. Morek then reclaimed all the lost regions.
