New Worlds: Structures of Marriage

(This post is part of my Patreon-supported New Worlds series.)

Having discussed who can get married and what they do it for, let’s talk about what shape the marriage can take — by which I mean how many people are in it, and how they’re officially connected to one another.

For most of us, monogamy is the most common structure (mono- meaning “one,” and -gamy meaning “marriage”). That is to say, someone in a monogamous marriage has only one spouse. That person is most commonly of the opposite sex, but not always, especially these days. But it’s worth remembering that unless you come from a religion or a culture that absolutely forbids remarriage after divorce or death, monogamy doesn’t mean having only one spouse, period; it means having only one at a time.

This stands in contrast to polygamy, i.e. many (or rather, multiple) spouses at once. We have a tendency to treat this word as if it means “multiple wives,” but it doesn’t: in fact, there are two more specific words to differentiate multiple wives (polygyny — the second part meaning “woman”) from multiple husbands (polyandry — “many men”).

The confusion probably arises because of the two, polygyny is the much more common structure. There are lots of reasons for this, many of them related to the patriarchal nature of most societies; when men hold power and women are treated as property, then it’s not surprising that the most powerful men will accumulate a larger share of that property to themselves. That doesn’t mean polyandrous societies are matriarchal, though. You see that pattern mostly in the Himalayas, where it’s a solution to the problem of inheritance and limited resources: dividing up the land between all your sons means pretty soon nobody will have enough to live on, so instead you marry all your sons to a single woman — fraternal polyandry. The land stays in one family, and there are fewer children, so you don’t wind up straining your resources. (Other societies accomplish the same end by shipping spare sons off to monasteries instead.)

Polygamy is illegal in the United States and many other Western countries. We tend to have a negative view of it in this country, associating the practice with Mormon fundamentalists in the Mountain West, living isolated from the outside world and engaging in abusive practices including, but not limited to, marrying adolescent girls to older men. It’s also found in some Muslim-majority countries, and used to be legal for Hindus in India until the mid-twentieth century, not to mention historical practices in Judaism — in fact, if you look at history, there are many parts of the world where it was once common.

Is polygynous marriage bad for women? That’s a difficult question to answer. It can be — but then again, so can monogamous marriage. Sometimes the senior wife is cruel and controlling toward the junior wives, but sometimes having co-wives is a source of comfort and support, especially when it comes to tasks like child-rearing. One of the sources I read when researching polyandry for Within the Sanctuary of Wings pointed out that being alone among a group of brothers can be incredibly isolating for women, contrasting that directly with the more female-dominated community of a polygynous marriage. In the end, it’s tough to disentangle the actual effects of polygyny from the surrounding tendencies toward patriarchy, away from female education, etc.

I do want to note, though, that what I’ve been discussing so far is polygamy in its more traditional sense, rather than the modern practice of polyamorous relationships (which in most cases can’t be legally recognized as marriages). The former is very much a setup where multiple people of one sex are married to a single person of the opposite sex, without necessarily implying relationships directly between the same-sex partners; the latter is often (though not always) more communal and egalitarian, and is sometimes termed “group marriage” instead, especially if there are sexual relationships between all the spouses. Line marriage, found in Heinlein’s fiction, is a variant on this where the marriage itself becomes a kind of lineage, adding new partners over time so that the family unit eventually contains none of the original founding spouses.

There’s also a separate-but-related subject in the form of concubinage and the keeping of official mistresses (or, more rarely, male lovers). That one is complex enough that I’ll save it for a later essay, but I want to note here that its more formalized version amounts to a type of polygamy wherein the junior women occupy an inferior status relative to the senior ones, and its less formalized version amounts to a type of polygamy with no legal recognition for anyone other than the official wife. Both have tended to be the province of wealthy and powerful men.

Which brings me around to the social effects of these different structures. I mentioned last week that one of the factors controlling who can get married is money; that’s even more true when multiple spouses enter the picture, because now you need to support even more people. When each wife is expected to maintain her own separate household — one of the methods used to reduce intra-family strife and competition — the outlay is substantial. Men in polygynous societies may take second wives for reasons ranging from status to political alliance to the need for an heir when the first wife is sick or infertile . . . but in such cases, the lament that they’re having trouble saving up enough money to afford that becomes very common.

And then consider supply and demand, so to speak. The human birthrate is basically 50/50 male/female. If some men are claiming multiple wives, that means other men have none. (Unless you have a society that is simultaneously polygynous and polyandrous. I don’t think that’s ever existed in reality, but now I want stories where it’s true.) This can work if you have a warlike society and a decent number of your men are getting killed in battle, skewing the overall gender balance toward women — and there’s a feedback loop there, because if you have a lot of young men running around without families of their own, the odds that they’re going to enter into violent conflicts go up, unless you stow them somewhere safe like a monastery.

It’s almost certainly going to be young men, too. Back when I talked about stages of life, I mentioned that power and influence (and money, though I didn’t say it there) tend to accumulate in the hands of elders. Spouses go hand-in-hand with such things. Couple that with the risk of dying young in childbirth, which has been a serious danger for women through much of history, and you inevitably wind up with lots of situations where older men are marrying much younger women. It doesn’t happen only because of patriarchal tendencies; it’s also the natural consequence of other factors.

So if you want to write about marriage structures other than the type of monogamy that’s common today, think about what factors will support that other structure, and what the effects of it are likely to be.

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About Marie Brennan

Marie Brennan is a former anthropologist and folklorist who shamelessly pillages her academic fields for inspiration. She recently misapplied her professors' hard work to the short novel Driftwood and Turning Darkness Into Light, a sequel to the Hugo Award-nominated Victorian adventure series The Memoirs of Lady Trent. She is the author of several other series, over sixty short stories, and the New Worlds series of worldbuilding guides; as half of M.A. Carrick, she has written The Mask of Mirrors, first in the Rook and Rose trilogy. For more information, visit, Twitter @swan_tower, or her Patreon.


New Worlds: Structures of Marriage — 15 Comments

  1. There is also biology–if there is a high infant mortality rate, for instance, and men in power want sons, collecting wives gives him a better chance of having those sons. There is one inescapable part of biology: it only takes the man minutes to do his part, but it takes a woman pretty much a year, or close to, for hers.

    • Yeah, that has a lot of knock-on effects. I once wrote a piece arguing that if you want your speculative society to have gender equality, one of the easiest levers to push on is the infant mortality rate: if most children survive to adulthood, then it’s a lot more feasible for women to spend their time doing things other than having children. Whereas if half of them die before the age of five, you need to put a lot of effort into keeping your population up (especially since that tends to go hand-in-hand with high maternal mortality, too).

      • A woman is not just out of the reproduction cycle for the 9 months of pregnancy. If she nurses a child until natural weaning as in a society without bottles and baby formula, she is most likely infertile for another 2 years. That extra two years gives her body a chance to recover from the ordeals of pregnancy and childbirth which also gives her a better chance of surviving the next pregnancy and childbirth.

        A man’s sperm recovers fully after about 3 days. A woman’s body recovers from babies in about 3 years. If a land is underpopulated this makes polygamy more understandable.

          • Breastfeeding as birth control is unreliable. My children were born just 16 months apart, and I honestly was too lazy to mess with formulae when my body was producing the right stuff at the right temperature at all times.

            The problem is, if you have three babies in four years, you become Missis Miscarriage. At least I did.

            Another thought, I tried the Pill but any kinds available made me anorexic and suicidal. Well, they were very effective as instead of having sex I just wanted to puke and die, however, a miscarriage once in a while was more pleasant. What if a whole society faced this dilemma?

            • Yes, “suppresses fertility” is not the same thing as “turns it off completely.”

              I’m really sorry to hear about the miscarriages and side effects.

              • No need to be sorry. Life happens and we are richer by the experience. And I have my three children, all grown up beautiful in their own ways. I suppose I have done better than women before medicine and contraception. At least once they were born alive they stayed alive.

      • I have speculated that gender equality is a good counterbalance for an overpopulated society as well, since women then have many options for ways to develop their lives besides bearing children. I’ve always thought it would be an interesting study to see how feminist movements correlate with the combination of reductions in child mortality, reductions in women’s mortality from childbirth, and the need to level off population growth. Of course, as a feminist, I could argue for systems that allow population growth without pushing women into limited roles, but that’s another issue.

        • My impression is that the three biggest factors which can lower birth rate are (not in order) 1) female education, 2) availability of birth control, and 3) electricity — because it turns out that if you give people the option of watching TV or otherwise entertaining themselves at night, they have a lot less sex . . .

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  3. Whenever I read my anthropology textbook, I was always surprised at how it cited the same circumstances & fear, to explain both Tibetan polyandry & English primogeniture (limited land & fear of subdividing the land into too-tiny-to-be-useful)

    > Sometimes the senior wife is cruel and controlling toward the junior wives, but sometimes having co-wives is a source of comfort and support
    I would guess that one factor is whether or not there is competition to see which wife’s child succeeds their father as the ruler (such as in pharonic times)…another factor being individual personality.

    • re: land — partible inheritance, where you split it equally among your children, really really sucks. In fact, it sucks enough that one of the anti-Catholic measures in England was the Gavelkind Act, which ruled that Catholic landowners had to pass on their property via partible inheritance . . . but Protestant landowners didn’t. Split up your estate, or convert and keep it intact: your choice.

      re: competition between wives — yes, the more it’s a zero-sum game between the wives, the more you will inevitably encourage that kind of cage match. (I’m re-watching Nirvana in Fire with my husband, and ye gods, the fight over the throne . . . which is driven as much by the mothers of the various princes as by the princes themselves.)

  4. “Sometimes the senior wife is cruel and controlling toward the junior wives, but sometimes having co-wives is a source of comfort and support”
    My great-grandfather had four wives in Yemen, though only one survived to journey with him to Israel (my great-grandmother). My grandmother claimed she was this kind of cruel woman, going so far as to say that she killed off the other three wives… but they had a very adversarial mother-in-law/daughter-in-law relationship, so I take this claim with a large grain of a salt.

    Also, I’m surprised you didn’t mention LeGuin’s Planet O, with its complex system of marriage, and her accurate comment: “It’s just as complicated as it sounds, but aren’t most marriages?”

    • My grandmother claimed she was this kind of cruel woman, going so far as to say that she killed off the other three wives… but they had a very adversarial mother-in-law/daughter-in-law relationship, so I take this claim with a large grain of a salt.

      I mean, not that one wife murdering another never happened . . . but yes, that sounds like it might be exaggerating. You would think your great-grandfather might have noticed the serial killer in the house.

      Also, I’m surprised you didn’t mention LeGuin’s Planet O, with its complex system of marriage, and her accurate comment: “It’s just as complicated as it sounds, but aren’t most marriages?”

      I’m aware of sedoretu, but now that I stop to think about it, I’m not sure I’ve ever read any of the stories with it! So it didn’t leap to mind.