Tech level of the society in general should be just about at the advent of the printing press--early enough that it's not seen as an absurd thing to copy out a book by hand. I'm handwaving the existence of some sort of vegetable-fiber paper (rice paper or the like, a la http://www.rice-paper.com/about/makeyourown.html ), because I want the area to have a long-standing tradition of both general literacy and specific scholarship. I don't think that would happen if there wasn't readily available, reasonably inexpensive material for writing on. One result of this is that every clan has, as a formal and respected role, the clan scholar. Said scholar is expected to teach the basics (literacy, maybe a little math and history) to all the children (probably, on average, to what we'd consider about the 4th grade level), as well as to tend (and where possible expand) the clan's library. A clan of any real wealth at all would be expected to have at least ~50 books, and some clan libraries number well into the triple digits.
In this region, the government is more or less a clan structure. The clan owns all the land, individual families own (legally defined) use-rights, which can be bought and sold. Farmers give up a predetermined fraction of the resulting crop as the "clan" share; this clan share is 1. used to feed laborers and the like who don't have their own land to farm, 2. used to support the clan heads and those in positions of special authority like the clan scholar, the herb-wife, and what not, 3. traded to obtain things the clan as a whole needs, and 4. held in reserve against lean times. The remainder is the farmer's to use, trade, save, or whatever. Your use-right can be confiscated if you are misusing the land, or commit certain crimes, and you are expected to consult with the clan's seneshal (or whoever) if you're going to do anything odd like plant a totally new crop, but generally you're left to work the land however you wish.
Gender roles are about similar to those we're familiar with (except that "scholar" is a basically unisex role), but they're not quite as absolute as was the case (afaik) in real history. That is, a female in a "male" role (like clan head, or warrior), or a male in a "female" role (like herb-wife or weaver) is seen as odd, and as somewhat less of a woman/man, but not as totally freakish--kind of like, say, how a lot of people today would treat a man who's a nurse, or a woman who's a construction worker.
Part of the reason for this relative equality is the existence of a reasonably effective and safe herbal birth control, euphemistically known as "Maiden's Ease". It is generally used more to delay/space children than to entirely prevent them, most women do marry and have kids sooner or later, but with this herb they can have them at planned times. And there is enough basic knowledge of medicine (at least, the vague concept of germ theory) that one does not have to churn out half a dozen children to have one live to adulthood.
Also, though marriage is generally expected when children are on the way, a single mother is...not an outcast or whatever, at least not automatically, particularly if she is in a gender-atypical role. And she's definitely not seen as "ruined"/inherently unmarriageable. There's sort of a sense that girls who don't have sex before marriage are more "proper", but there's not really any kind of slut-shaming going on.
For the leadership of the clans, instead of having strict primogeniture or whatever, one's heir is selected and formally placed in the role (usually somewhere in his (or her) late teens) shortly after one is one's self made the clan head. The heir has traditionally defined spheres of authority (relatively limited), and can be delegated greater authority on a temporary basis from the present clan head--which is usually done more and more often, as the heir gains experience and the clan head grows older. It is typical (though not universal) for the clan head to formally retire when his heir's heir is ready to assume the role. The heir is typically, though not formally or universally, the eldest son or eldest child of the clan head. And the heir (less often the clan head) can be kicked out by consensus of the rest of the clan.
One is considered a formal, full adult, with all rights and privileges, at 16. But, from the age of 12, one can... legally function as an adult, in emergency situations. For example, if the present clan head dies when his heir's preferred heir is under 12, the new clan head has to chose someone else to be his heir. But if the prospective heir is between 12 and 16, he can be made the heir, even though he's not a full adult yet. Similarly, a 12-15-year-old who gets pregnant, or gets someone pregnant, would usually be expected to marry, though normally people don't marry until 16 or later, more typically 20-25. Inheritance of farming-rights tends to take place around the time that one's preferred heir is starting his (or her) own family, with the older couple more or less "retiring" to a less active role--they will usually continue to work the farm, but leave more strenuous or troublesome chores to their replacements.
The prevailing religion is probably not entirely unlike what you'd get if you mixed Christianity, Judaism, Wicca, and a touch of ancestor reverence in a blender [g]. It's a "book" religion, where every reasonably devout person is expected to read and understand the Book themselves. Priests are not necessarily needed around on a day-to-day, or even week-to-week basis, though they do perform major ceremonies like weddings, funerals, and baptisms. In some cases, another individual--usually either the clan head or the clan scholar--can kind of act as an emergency substitute. There are conversions, though, and at least some effort is made to proselytize and spread the faith. The religion has 2 deities, the Lord and Lady. For the most part, though praise and worship are directed to the Lord and Lady, one generally makes any requests/prayers for intersession by asking one's deceased ancestors, or other dead people one was close to or respected/admired, to speak on one's behalf. This can include dead saints, but you generally only call on them if either you have no dead relatives, or you're in dire straits and are asking everyone for help...
Our story is set in a valley, occupied by 2 (currently feuding) clans. The valley is along a (relatively minor) trade route, and is slightly elongated, with tapered ends. The border between the two clans is along the middle--er, lemme try to ascii-art it. <=|=> Like that. The keep for each clan is not quite halfway between the border and the end of the valley (closer to the border). The keeps are somewhere around an hour (at a fast walk/horse ride) from the border. Each keep has (marginally) enough room to fit the entire clan at once; most of the clan will stay there during the winter, when fewer people need to be doing farm chores, as it's more efficient to just warm the keep, not every farmer's house (particularly for children, old people, pregnant women, and anyone else that might be more delicate than usual). Each clan has ~100 families in it.
The valley has a river running along the middle (perpendicular to the clan border). There is a cave near the clan border, at least large enough to hold 10-20 people. The climate is cool enough that it usually snows at least a few times every winter, but not so cold that the terrain typically becomes impassible. So, the feud is mostly conducted during the winter, so that farmers can concentrate on farming during the summer.
Our Heroine is the 15-year-old clan scholar. She is the youngest of 5 children of the clan head, only 2 of whom (her, and her oldest brother who is the heir) are still alive.
She inherited her position from her grandfather, also deceased. All of the deceased individuals just listed died from the feud, not from natural causes.
Her routine duties include maintenance of books and records, making her writing supplies (paper, ink, pens), and teaching children in winter. I suspect I know what book maintenance would consist of (sewing damaged bindings, looking for mold or other problems, possibly oiling leather bindings) I'm not sure, however, if there's any historically appropriate ink that would work well for making things for long-term use, as carbon inks apparently don't last well, and iron gall inks kind of destroy the paper (so saith http://en.wikipedia.org/wiki/Ink ). And I'm not positive that paper making as described above would be reasonably plausible for the tech level and her capacities. And I'm not sure if she'd make quill pens, or some other type of pens. And, in any case, I'm not sure if paper, pens, and ink would be something she'd make herself, or something she'd buy from traders. And, well, I'm not really sure how to search for more info on this.
And, if anyone else has any ideas of day-to-day stuff that I wouldn't have thought of, please feel free to throw those in, too.
edit: I was using "keep" in the sort of vague sense of "fortified place where everyone can live".
And the feud started because of a demon, and has since been a revenge cycle...