I thought of combining numbers for both upper and lower levels, but on second thought, I decided it would be better to provide both separately, and then the combined data at the very end. This will make for a rather long and dull series of stats. A few comments should help flesh out these numbers.
Now, do hang on to your shields!
This is a nation of windswept mountain peaks, deserted glaciers, and deep, dark valleys. With a population density of 3 people per square mile, few will be rubbing shoulders outside urban centers. The vast majority of the population is concentrated in the river valleys in the realm's southern half.
Considering how woefully spread out Upper Stoutfellow's army is, it remains vulnerable to any concentrated attack. However, Upper Stoutfellow seems strikingly iceberg-like. . . Alright, that was a bad pun, but the image is correct. A look at what lies beneath the surface and how quickly it might emerge should help one reconsider that assessment. On the other hand, Stoutfellow has no naval warfleet--not one teensy-weensy little raft. The idea of taking to the sea invariably sinks like a rock among dwarves and gnomes. Halfling pirates will have to look for opportunities elsewhere.
Business-wise, this is a prosperous nation. Notice how little income derives from direct taxation. More than half the upper realm's funding comes from trade. Gnomes run major banking and gem-cutting operations, while halflings produce outstanding agricultural goods, including massive quantities of pipeweed and fine ale. Dwarves hold much of the mining and military-related industry.
Let's now see what lies under the hood.
The first thing is that lowlanders outnumber highlanders two-to-one, and they are even wealthier. Endless miles of moss farms and fungal forests, and a huge lake easily support a boisterous population 96% dwarven. Despite this, a population density of 7 people per square mile isn't exactly "crowded" compared to places like Ambur or Stonewall. Settlements center on the "green areas," while mountainous and stalagmite-filled areas remain essentially deserted. The present area figure (which is comparable to the surface realm) includes the great lakes, but not the Great Swammholt and the Trench. Although claimed by Stoutfellow, they haven't begun to settle it and thus do not control it, save for a tiny portion in the west and on top of the two cliffs overlooking the Trench.
Although not at war with other "recognized" states, Stoutfellow is in fact engaged in a long-term armed struggle. The main enemies are trolls from the Trollmark and the enigmatic denizens of Shadow Deep. As a result, Lower Stoutfellow has grown into a militocracy, with more than 5% of its citizens in the army. Nothing less will suffice to properly defend the strongholds locking the various cave complexes, and the fortified gates leading to the surface. The Dragon Express was deployed initially to move reinforcements and supplies very quickly to most parts of the realm. Furthermore, mechanical elevators have been installed to lift troops to the surface either through the Denwarf-Hurgon city-pillar or the fortified gates. An army of battle-scarred, grizzled dwarven veterans specialized in cave or mountain warfare is more than enough to stop an invader unwise enough to set foot upon this harsh land.
Life is more expensive down below, but then the standard of living is much higher. As with Upper Stoutfellow, direct taxation of the population remains at a minimum. Here, more than 60% of state revenues come from mining (generated by less than 9% of lowlanders.) Agriculture is sufficient to support mining communities and urban centers, allowing excess farming goods grown on the surface to be exported, mainly by ship from Bral to Draco.
Just for kicks, I tallied all the data, combining Upper and Lower Stoutfellow, as follows:
With nearly three quarters of a million Stoutfellows, we're well past original 60,000 figure from DotE. I've remained pretty faithful otherwise to the description of Denwarf-Hurgon. Come to think of it, I was toying with the idea that the upper city's name should be just "Denwarf" (Rockborn) and the lower city, "Hurgon" (Cavern.) As a whole, it is otherwise known as Denwarf-Hurgon, especially by outlanders.
I hope all these stats answered questions you had about this unusual realm, or perhaps it sparked even more. Next stop: the stats for Denwarf-Hurgon, both ends of it, naturally!