This is incorrect. The ruler can be a lord if he is also a duke. He can then appoint himself as a lord of a region in his duchy.
The ruler just can't be a lord of a region in which he is not also the duke.
Except that he can't create new duchies for himself, and therefore must wait for a duke to abdicate to take his spot. A rare occurrence, and usually unforgivable in most realms.
Also, peasants just kicked out a lord because of a big horde that had bothered them for a few days. I can't appoint him back.
We also got a noble of Melhed who just joined a few days ago, but has apprently been in the realm for 60 days or so according to the character list.
