I decided that I will actually run a (heavily modified) version of the Wilderlands for my home group. It will be based on the events of my early college campaigns, as well as some other stuff I think is neat. You will notice some "misspellings" in the text below. These represent my initial mispronunciations of certain words (Pazidun Peninsula, Tharabians, etc.) based on my semi-dyslexic reading of the original setting.
The City State of the Invincible Overlord
The City State of the Invincible Overlord was all but destroyed many years ago when a great automaton, a relic of the Uttermost War, erupted from the Earth and attacked the city. The thing was stopped by a group of adventurers, who have since passed into legend and are sometimes revered as a kind of mini-pantheon known as the Comitatus. The overlord of the past several years, Bjorn the Mighty, a Skandik demi-god rumored to himself be a member of the Comitatus, has rebuilt the city and brought the Skandik kingdoms of Ossary and Croy to heel. The culture of the CSIO is largely based on 3rd century Rome, with Tharabian and Skandik troops acting as auxiliaries in its legions. It is still primarily a city state, and Ossary, Croy, and the other kingdoms within its influence are protectorates, not provinces.
The Empire of Vridistan (the City State of the World Emperor)
Viridistan acts as the chief rival to the CSIO. The Viridian Emperor's territory is apparently large, streatching from the Desert Lands to the Elphand lands, and having recently acquired some lands in the Eastern part of the Roglaras when the CSIO was being rebuilt. However, his grip over these areas is weak, and the individual satraps possess a great deal of power. As the name and some of the nomenclature hints at, the Viridians resemble the Achaemenid Persians culturally, complete with Immortals. However, the Viridians are a tiny, disappearing minority and the bulk of the population is Tharabian (Celtic) or Ghinorian (Greek).
Conan, or perhaps Konahn, land. The barbarians here have skin of vaguely red or violet hues, showing their possible relationship to the ancient Orichans of old. They often raid into the lands of Viridistan and the Skandiks.
Antil is the City of Slavers and primarily serves as generic sword & sorcery bad guy fodder. They are bald and tend to eschew the historical armor more commonly found in the other areas of my Wilderlands for stupid Red Sonja bad guy style get ups.
The Kingdom of Oricha once stretched the entirety of the Pazidun Peninsula. Its rulers were said to be men descended from demons with blood red or violet skin and raven black hair. Their descendents supposedly live on in Barbarian Altanis, but their culture was destroyed long ago during the rise of the Kingdom of Kelnore and the arrival of the Tharbrians to the Roglaras. It is thought by some that the CSIO may have been Oricha's capital. Their culture and ruins are vaguely Egyptian in a kinda weird, Hollow Earth conspiracy theory sort of way.
Ghinor is the common tongue's name for the ancient Kingdom of Kelnore, which at its height stretched almost across the entirety of the Wilderlands. The kingdom fell, much like Oricha, with the rise of two new kingdoms (Viridistan and Tarantis) and the arrival of barbarians (the Skandiks). The southern areas of the Wilderlands still possess a number of Ghinorian successor states, most of which have either pseudo-Hellenistic cultures (though some may be more like early Byzantine).
This frozen land marks is dominated by the Elphand Province of Viridistan, a rather rebellious region that is notoriously difficult to run. It is sometimes given to extremely competent satraps in the hopes that they will be able to cement Viridian influence there, and sometimes given to those out of favor with the Emperor as a sort of exile. The northernmost section remains independent, and the city of Damkina - an isolated Ghinorian successor state with a vaguely Kievan Rus-style culture - has, on a few occasions, been able to rally the northern villages together to resist Viridian incursions.
The Great Forest
This large section of the Elphand lands was once home to a great Elven empire, created supposedly only shortly after the Uttermost War, though times the chronology for events that distant is often hard to pin down. It is now home to a few petty elf kingdoms and a strangely large number of cave-men, morlocks, and other strangely-human like beasts.
Valon was once an outpost of the Elven Kingdom of the Great Forest, though now it is mainly ruled by men (and a large number of half-elves). These men share the blue skin of the Northern elves, hinting at their mixed ancestry. It is a beacon of civilization in an otherwise barbaric wilderness, though this means it is also vulnerable to the excesses of Wilderlands civilizations, particularly slavery. Like the Tharabians, Avalonian culture is vaguely Celtic, though perhaps more reminiscent of medieval Ireland than the Gauls.
Tarsh is a largely ruined city that once stood at the head of a great kingdom in the North. It was once a protectorate, though not a direct part, of the Kingdom of Kelnore. When combined with its strange, star-gazing druids, the overall effect is rather like Mithridatic Pontus. With the collapse of the Ghinorians in the face of other kingdoms and barbarians, the strange priests of Tarsh turned inwards to investigate the magical properties of the heavens and of bizarre gates that liter the area.
The Valley of the Ancients
This infamous valley is filled with ruins that predate even ancient Oricha, some even going back before the Uttermost War. This is where you get ray guns.
Tarantis is a vaguely Seljuk protectorate of the Kingdom of Karak, known for its pirates and occasionally for its Sinbad-style sailors.
The Kingdom of Karak
Karak is a vaguely Mongolian kingdom whose territories in the Wilderlands include Tarantis and the Ebony Coast. While the urban centers of their kingdom tend to be in the south, the Karakhans themselves spend much of their time on the Glow Worm steppes, where they keep their horses and live their traditional nomadic lifestyles when not holding court.
The Desert Lands
This is another rebellious province of Viridistan, centered around the Holy Cities of Mycr, a strange monotheistic deity rarely worshiped outside these lands. Mycretians loathe the Viridians but their priests urge pacifism, leading to a number of odd forms of resistance. The holy cities are supposedly connected by miles of underground passages, complete with shrines and even a sacred fire sometimes purported to be Mycr himself.
A Ghinorian successor state at the edge of a steaming jungle, Lenap is very similar to the Ilionians of Uz - that is, they are Greeks who have a large number of strangely Mayan affectations as well as a cultural fascination with dinosaurs.
I'm probably going to redraw the map immediately around the campaign area (haven't decided if that's going to be the CSIO or not yet), replacing or renaming settlements in order to make the aforementioned cultures show up more clearly. I like the Wilderlands, but I think it suffers from being nonsensical culturally unless the DM puts some extra work into it.