The medieval evidence is sketchier. But to me it paints a similar picture. Gregory of Tours starts his 6th-century History of the Franks: "I recount for you … the holy deeds of the saints and the way in which whole races of people were butchered." Among other things, King Guntram is said to have killed his second wife's half-brothers for making "hateful and abominable remarks" about the queen; and King Chilperic, having levied "extremely heavy" taxes, is supposed to have punished people who plotted to kill the collector by "having them tortured and even put to death out of hand." In England, William of Malmesbury's 12th-century Chronicle of the Kings of England tells more horrible stories. Hardecanute, in the 11th century, reputedly ordered Worcester plundered and burned because of two of his tax collectors were killed there; and Henry I, in the 12th century, punished transgressions among his court "by a heavy pecuniary fine, or loss of life."

Bishops, of whom Gregory of Tours was one, were no better–particularly to those who opposed them. Gregory describes two, Salonius and Sagittarius, who were "no sooner raised to the episcopate than their new power went to their heads." Gregory says they sent a mob to attack another bishop having a birthday party; they beat their own congregations with sticks; and, overall, "with a sort of insane fury they began to disgrace themselves in peculation, physical assaults, murders, adultery and every crime in the calendar."

Medieval polygyny? Certainly not. Everybody, even the most eminent of medieval historians, knows that polygyny was stopped by the Catholic Church. I don't think so. I think Jack Goody, who wrote a famous book called The Development of the Family and Marriage in Europe, was right: I think the quarrel between church and state in the Middle Ages was about marriage (which has to do with things like inheritance and succession), not about mating (which has to do with sex). I think the sketchy evidence suggest medieval priests and lords, cardinals and kings, quibbled about marriage, and went about their merry polygynous ways.

According to a cleric named Lambert, whose Historia comitum Ghisnensium is a 13th-century account of his benefactor, Count Baudouin: "From the beginning of adolescence until his old age, his loins were stirred by the intemperance of an impatient libidoe … ; very young girls, and especially virgins, aroused his desire." Baudouin's bedchamber, in the most inaccessible part of his castle, had direct access to his servant girls' quarters, to the rooms of the adolescent girls upstairs and to the nursery–which Lambert's 20th-century resurrector, the French historian Georges Duby, calls "a veritable incubator for the suckling infants." Baudouin was buried with 23 bastards in attendance, besides 10 living legitimate daughters and sons; these are likely, as Duby says, to have been fruits of just the family tree's primary limbs.

Literary sources raise the possibility that young women were kept apart in gynaecea or chambres des dames–women's quarters or ladies' chambers–where they entertained the lord of the house (and no one else) and made shirts. Even census records suggest, as the eminent medievalist David Herlihy put it, that "women tended to congregate in the households of the powerful, even on monastic estates." Down to the nitty-gritty level, if parish records from late medieval Tuscany and England are right, rich men's houses held more women and children than poor men's houses.

It was as late as 1840 when Alexis de Tocqueville, in Democracy in America, wrote: "I go back from age to age up to the remotest antiquity, but I find no parallel to what is occurring before my eyes." He meant, of course, the fall of kings and rise of the common man. I won't chronicle the rise of democracy in modern England–to tell you the truth, I haven't got that far. But I'll hint that polygyny might have declined, nice and gradually, at about the same time.

William of Malmesbury's Chronicle is full of the usual epithets–like "polluted by his lusts," "abused the beauty of his person in illicit intercourse," and "wholly given up to wine and women." Kings and princes have always been (still are) notorious for affairs with high-ranking women; many owned up to having got high-ranking bastards by them. But if affairs in early modern England were like they've been everywhere else, then peers and gentry should have had sex with, and probably got bastards by, lower-ranking, less well-remembered women as well. In Rome, many of those women may have been slaves. In England, many of those women may have been maids.

Lawrence Stone, the world's authority on the sex lives of the British upper class, scrutinized six early modern diaries. They leave the distinct impression that sex was easy to get. Respectable married women may have been relatively hard to come by, but actresses were accessible; so were "shirt and ruffle makers," high-class whores, women in brothels and women on the street. Last, but not least, "there were the poor amateurs, the ubiquitous maids, waiting on masters and guests in lodgings, in the home, in inns; young girls whose virtue was always uncertain and was constantly under attack." Stone adds: "These last were the most exploited, and most defenseless, of the various kinds of women whose sexual services might be obtained by a man of quality."

If he's right, then polygyny in early modern England–as in other places and times–should roughly have paralleled household size. Life-cycle service–by which young men and women spent the flower of their youth in relatively wealthy households–was a long-standing pattern in Britain. Domestic servants, in particluar, tended to be young, unmarried, and female. More than half the population aged 15-24 was "in service." Most "productive" servants–in apprenticeships or on farms–were boys, while most domestic servants–at work in their masters' homes–were girls. Over the last few centuries, British domestic servant staffs shrank. Dramatically. In the early 16th century, for instance, men like the Earl of Northumberland, or Cardinal Wolsey, had several hundred–as many as 400–domestic servants on their main estates. Numbers stayed high–in the hundreds–to the late 16th- early 17th century. Then they started to drop. By the mid-17th century, most large estate staffs were down to 30 to 50. In Gregory King's Scheme of the Income and Expense of the Several Families of England for 1688, maximum mean household size ranged from just 8 for gentlemen, 10 for esquires, 13 for knights, and up to 40 for temporal lords. By the mid 20th century, servants had all been wiped out. According to Richard Wall who–along with an army of volunteers and academics at the Cambridge Group for the History of Population and Social Structure–has analyzed hundreds of parish records, there were 61 servants per hundred households in England in the late 17th century, 51 in the late 18th century, from 14 (urban) to 33 (rural) in the mid-19th century, 2 in 1947, and zero in 1970. If my guess is right, those shrinking staffs meant shrinking sexual access–read, polygyny–by the British aristocracy.

What about us? Has the United States been, from the beginning, a two-strictly-monogamous-parents-plus-kids populist democracy? Not really. In the debate over the US Constitution, for instance, Alexander Hamilton–future secretary of the treasury said, according to James Madison's Notes: "Let one branch of the Legislature hold their places for life, or at least during good behavior. Let the Executive also be for life." Even moderates like Madison in The Federalist Papers said things like: "Liberty may be endangered by the abuses of power…; the former, rather than the latter, is apparently most to be apprehended by the United States."

In 1787, at ratification, voting rights were determined by state–and limited in most by sex, race, and wealth. In Virginia, suffrage was given to white men over 21 who owned 50 acres of improved land, or a town lot, or were employed as artisans in Richmond or Williamsburg; in South Carolina, voters were white men over 21 worth at least £500 worth of land. Property qualifications were gone within about a generation. But not until nearly a hundred years later, in 1870, did the 15th Amendment let men vote regardless of "race, color or previous conditions of servitude"; 50 years after that, in 1920, the 19th Amendment extended suffrage to women.

Loath as I am to spread slander about our forefathers, let me suggest that the membership in the early American aristocracy may have had its sexual privileges, too. Well-to-do pre-abolition US households hired servants or owned slaves. There was gossip about miscegenation. Charles Lyell, for instance, noticed in his Travels in the United States that "the anxiety of parents for their sons, and a contant fear of their licentious intercourse with slaves, is painfully great"; and a sister of Madison is said by Arthur Calhoun to have remarked, "We southern ladies are complimented with the name of wives, but we are only the mistresses of seraglios." After abolition, the household staffs of American aristocrats–like those of English aristocrats–shrank. Rich men might have had to leave home more often, at least.

Which reminds me. Have you ever heard the one about Thomas Jefferson? Ben Franklin? George Washington? Apocryphal stories never end.

Laura Betzig, co-director of the Evolution and Human Behavior Program, is the author of many scholarly articles and the study Despotism and Differential Reproduction, A Darwinian View of History (Aldine, New York, 1986).