In such a society there are a few things you need to consider:
The Gods Meant Everything
One god made the sun rise in the morning, another god made sure the rain falls so that the crops can grow, another god makes sure the lands stay bountiful and the soil stayed dark, and rich. In primitive cultures, most gods started off as Fertility gods of the earth, adn evertually gained a more defined role as the cultures became more defined. Taken into context, Ares of the greek god of war was a fertility god who might have been, more specifically and further back into history, a god of war focused on gaining mroe land so more food could be grown, and eventually, as the greek civilizationa arose, lost most of the 'fertility' part of his portfolio, and became more achetypically warlike. Athena might figure out the best ways of argriculture; eventually she is the goddess of Wisdom and riddle-solving. Etc.
So, the gods in this setting would basically all be very earthy deities, with portfolios closely tied to agriculture and fertility.
The World is Brutal
Mankind and it's kindred are just learning the most primitive ways of agriculture, maybe just a generation or two ago. Famines are devastating, starvation is likely, and survival of the fittest menas that if you step up to the challenge
you're the one who gets to ive tomorrow. It's kill or be killed; man is just another animal, really. Sure, one with tools, and weapons and gardens, but a dirty, pathetic, weak animal. Cheifs rule the roost, and mentalities are likely like wolves: BIG CHEIF gets his fill first, them the hunters, then big cheifs wives, then warrior wives, then the other men, then the other women, then the children, then the elderly, then the sickly. If the sickly were lucky if therewas a food sthortage, the tribe would bash their head in with a rock before the hunger pangs made their stomach bloat up, their legs tuirn to sticks, their faces turned gaunt and they eventually, after a long and agonizing period, died.
Hunting parties provide the meat and make tools and food from every aviliable resource. Native Americans and the Dark Sun campaign setting are some
really good references for this sort of stuff. Native Americans used buffalo stomachs for waterskins, since they would swell up like balloons and hold 1-2 gallons of water or somesuch (If you're a Canuck like me, that's 4-8 liters). In Dark Sun, giant bugs carapaces become useful in crafting armous and the like. Every man would liekly have to craft his own weapons and any protective materials he might wear; there wouldn't be a village smithy or the like (though there would likely be a fellow in that tribe who had a great knowledge of weaponcraft who teaches the rest). Woman and children work in the fields all day, and would run the households. Liekly, they'd have an equal say in what goes on in a village if they're more, ahem, "democratic", although "tyrant" chiefs would be more common, especially in more primative villages with more hunting and less gathering.
Bartering Gets You What You Need
Very few societies in the stone age had an sort of monetary system. Things were traded, ie "a sack of grain for two chickens". This means that if you want something, you'd better have something that the person you are trading needs or wants. Yes, this could mean that Craft: Basketweaving actually becomes useful, since baskets would be useful in the stone age. Primitive clay works would be uncommon, but availible; mostly you'd use animal parts or the land around you to make and get what you want.
Moreso, being a someone becomes more important that making the best trades. If you slay a big, nasty critter, you gain the respect of the tribe. Maybe you get a fourth wife, maybe you are giving gifts of food and words of thanks from the cheif, maybe there is a celebration thanking the gods and praising you for your deeds. Roleplaying becomes essential here, in game terms. You gain respect, and this effects how the rest of society veiws you, and becomes more powerful than anyhting "money could buy". The cheif praises you, and you should feel humbled. The gods sing a joyous song for you, and you should feel like the tallest man in the world. The villages fawns its' mighty warrior, and you should look to the next day, where your life might be ended or your stories and tales of heroics might be told millenia from that day.
Geography Was Everything
Most likely, you should be in a verdant and ferile area if you want to give rise to civilization. History shows us that the Indus Valley (for East Indians), the Nile River and its' delta (AEgyptians), Mesopotamia (Sumerians and their decendants) and the Chinese river valley (forgetting it's name) were all similar.
So, why does this mean that they fostered so much life? See the title of this section.
You see, if you have man, which is turning slowly into a farming civlization from a race of hunters and gatherers, you need an area which is going be able to most easily grow crops, and thus give you back the most food for the effort you put into farming. It's really that simple. Thus, an area with such rich soils as river valleys, is going to be able to give farmers bountiful crops, thus less work, thus happier people with more time to refine and improve their culture. Slaves also help this bit out, and it should be noted that the greek civilization was based upn slavery to a large degree. Ever wonder who Plato and Aristotle had so much time to think upon things in the way their did? Well, they had slaves which made and brought them food, and clothes them, and kept up their quaters, and everything else. So, making that a bit more 'primative', you'd want slaves to farm for you so your wives could tame onagers for hauling, and so that the men could tame wolves for guarding their houses, etc.
In any case, that's about all I have at the moment, but rest assured: I would play in a well set-out campaign like this in a flash, and by no means would this be impossible to pull off. You just need to read a couple history textbooks and the like
cheers,
--N