Interesting take on this idea Aldarron.

I'm not really sure where the name Northern Delving first appeared, but my impression was that it was simply a name for the various dwarven settlements within Blackmoor.

I can see how it would extend beyond that though. Dwarves did definately come from the south. We can be pretty sure that there are dwarves in Thonia. In my campaign, dwarves originally came from a continent to the far west, passing through Thonia before settling near Blackmoor.

Havard