I think Nemesis recruited him to keep Khazar busy while he built up his power base on land 5. Whether it was through placating him or outright threats is up to your imagination, I'd believe.
I have the Black & White Deluxe Edition on CD. There's a "making of" PDF on it that has pictures of the humans as creatures and the map when they were still using a lot of the Dungeon Keeper stuff. I'll post it up as soon as I get around to it.