Without giving too much away cause it isn't OGL, There are several different backgrounds, or "origins" your character comes from. The All Americian is the standard 1 xtra feat / 4 extra skill points at 1st level type human. But then the other origins are given other "origin" (insert: race) benefits inplace of the standard. Here are just a couple of examples of those varriants from the standard human of the PHB:
Aristocrat: +2 CHA, -2 STR, +2 origin bonus to Knowledge (high society) and Profession (management)
Cloistered: +2 WIS -2 CHR, free feat Skill emphisis (skill focus but +3 instead of +2) , rigouious traning grants a +2 origin bonus to REF, FORT, or WILL.
On the Run: +2 origin bonus to spot, listen, bluff; +1 luck bonus to all saves
Primative: +2 origin bonus to Handle animal checks; +4 origin bonus to Wilderness lore checks; free feat Weapon Proficiency (primative).
It is not all inclusive, (Erik Mona if you are reading, I still love Pulp Heroes

) but I think you get the flow.
Heck, you could even go the easy way, and take the races like dwarf, elf, halfling, etc., remove the names and physical descriptions like X feet tall, pointed ears etc., and give them names to the certain cultures you establish. It would take a little tweaking (size S characters get a bonus to hit and AC, so that might need some kind of compensation there)
Hope that helps.