Like I said at Mortality...
Here's a copy of the post I made at Mongoose's discussion board:
I must agree that a Quintessential Human book would be a very good idea.
But I think we should focus primarily on cultural variation rather then genetic variation. Look at how Oriental Adventures handled the various Rokugani Major Clans: genetically speaking, they're all similar. No stat variation, no special abilities, etc. But each Clan has different class skill options and favored classes. The Dragon Clan members have Knowledge (History) as a class skill and Monk as favored class, while the Scorpion Clan's members have Bluff as class skill and Rogue as favored Class.
If such a book should contain "subraces", they should be focused on cultural variation, not genetic mutation.
here's my list of how we should be dividing the various "subraces" of humanity:
Wild Humans:
-Jungle/Savannah Tribes (aborigine, african/native american tribes).
Tribe Structure
Wilderness Lore as a Class Skill
Favored Class: Ranger
-Plainsmen (The Mongols, the Plain Indians)
Clan Structure
Ride as Class Skills
Favored Class: Barbarian
-Desert Tribes (Sahara Bedouins.)
Tribe or Clan Structure
Wilderness Lore as Class Skills
Favored Class: Barbarian
-Arctic Tribes (Inuit)
Tribe Structure
Wilderness Lore as Class Skills
Favored Class: Ranger
-Island Tribes (polynesians)
Tribe Structure
Swim as Class Skill
Favored Class: Barbarian
Iron/Dark Age Humans
-Middle Eastern Empires (Babylon, Egypt, Sumeria)
Theocracy
Knowledge (Religion) as Class Skill
Favored Class: Cleric
[These societies are focused almost entirely around their priesthoods, with the ruler being consideres semi-divine]
-Greco-Roman Empires (Athens, Sparta, Rome)
Republic or Monarchy
Diplomacy as Class Skill
Favored Class: Fighter
[These are societies that are centered around a civil order rather then a religious one. While these societies are often chauvanistic and militaristic, explaining the Favored Class, a person's position is dependant on one's ability to form alliances with others, hence Diplomacy]
-Barbarian Clans (Celts, Germanic Tribes)
Clan Structure
Wilderness Lore as Class Skill
Favored Class: Barbarian
[These are tribes centered around a warrior caste with a fierce code of honor and conduct. Where more "civilized" folks compromise their honor for political alliances, a Barbarian would choose death before dishonor]
Medieval Humans
-Northerners (Vikings)
Clan Structure
Profession (Sailor) as Class Skill
Favored Class: Barbarian
-Dark Age Kingdoms (Saxon and Frankish Kingdoms)
Monarchy, Clan Structure, early Feudalism
Knowledge (War) as Class Skill
Favored Class: Fighter
[This is the dawn of the age of Chivalry, when the Feudal system began to solidify: Warlords became Kings, and began appointing loyal warriors to subordinate positions of power, such as Baronies and Knighthoods.]
-High Feudal (Arthurian, The Normans, The Holy Roman Empire)
Monarchy, Feudalism
Knowledge (Heraldry) as a Class Skill
Favored Class: Fighter
[By this point, the Feudal System is now firmly in place, with noble families passing titles and powers down family lines. Warfare becomes mixed with politics, and alliances are once again important. Knowing Heraldry is important, as allies and enemies are identified by their Crests]
-Kingdoms of the Holy Lands (Arabic Kingdoms, Turkish Empire)
Monarchy, Feudalism, Theocracy
Knowledge (Religion) as a Class Skill
Favored Class: Fighter
[At the same time as Feudal Europe, the Middle East becomes unified under a singular monotheistic faith. Adherance to the Faith is the mark of citizenship, and knowledge of religious rules is vital. Defense of the Faith and the Faithful and the desire to spread the Faith lead to increased militarisation.]
Humans of Exotic Lands
-The Land of Magic (Thay, Netheril)
Magocracy
Knowledge (Arcana) as a Class Skill
Favored Class: Wizard
[These are Human Cultures that have embraced Arcane Magic and the art of Wizardry as a way of life. Wizards and Magic Items are much more common in this culture,]
-Evil Human Kingdoms (Marmo, Thay, The Empire of Iuz)
Just take a pre-existing cultural template, and make the alignment of choice Evil.
[These represents those Kingdoms ruled over by Evil, which represent threats to all good and decent kingdoms, or just about any non-evil kingdom, for that matter.]
-The City of Sin (Think your favorie Pirate Town or City of Thieves)
Varied
Bluff as a Class Skill
Favored Class: Rogue
[These cities are filled with cut-throat bandits just waiting for an opportunity to get rich at the expense of another, most often between one another. Betrayal and double-dealing are the order of the day, and everyone's got an angle.]
-The Technocratic Empire
Varied
Knowledge (Machinery) as a Class Skill
Favored Class: Expert (or Wizard)
[These are civilisations that have made discoveries pushing their level of technology far beyond that of others. Generally, this means Clockwork or Steampunk technology far ahead of it's times. Othertimes, it is combined with the Land of Magic to create a society where Magical Constructs are far ahead of every other land.]
Well, these are the only Human-Oriented exemples I can think of right now. Further cultures, like the Aztek or Imperial China, can be created by altering one of the above templates. The Aztek are a Theocracy built around Human Sacrifice, for exemple. And China, during it's long history, has gone through the various Feudal stages many times, the actual Empire co-existing with various "barbarian" tribes in the same territory.
I recommend you folks check out Archetypology 101: Human, All too Human, which has a very good analysis of how to handle Humanity in fantasy settings.
Edit: Now that I've re-read my post, I realize a lot of these cultures are Barbarian-focused. ...I guess that old Conan saying is true: "Barbarianism is the True Nature of Mankind"