So I'm starting to wonder how much of modern Western sexual progress has coincided with modern Western "bourgeoise" trends in housing.Historically, many people just had no choice about where and when to do it. In premodern times, people's sensibilities were quite frank, and sex was not nearly as private. The whole notion of "privacy," for that matter, is quite modern. People did try to be somewhat secretive about their activities, which meant that sex would often be rather furtive and fast, but no one expected sex to be wholly hidden.
This changed with the advent of the bourgeoisie and the birth of modern notions of privacy. The more prosperous classes promoted an idea of sexual discretion, and they had enough space to conform to it. Parents and children slept in separate rooms, and the idea of shielding kids from their parents' sex lives became prevalent enough that Freud could write of a child viewing the "primal scene" as a traumatic event.
But space remained at a premium for the poor, and their housing actually grew worse as industrialization advanced and poor people flocked to the cities in hope of work. The urban working class often suffered much worse crowding than rural people did. In 1918, half of the apartments in Berlin, Germany, had just one room. The situation was worse in some other European cities. Poor women commonly rented out (part of) a bed to unrelated tenants, which meant that the family's young daughters might share a bed with a young, unmarried man. About a third of 5000 poor housewives surveyed in Berlin in the early 1930s had sublet arrangements with boarders.
I know a little about this issue from my research on the history of childbirth. As you might imagine, the lack of space and privacy also became an issue at the other end of the pipe, so to speak. A one-room apartment doesn't allow for a hygienic home birth by modern standards. Nor does it facilitate the sort of privacy that doctors and midwives increasingly saw as morally necessary in childbirth. This was a big factor driving women's choice to give birth in hospitals.
The key term here is "bourgeois," both morally and materially. In the 1920s, middle-class housing reformers pushed for better apartments for the poor - not necessarily larger but chopped into fewer rooms - partly because they saw morality endangered by the lack of privacy. This seems to have been a much bigger deal for the middle-class do-gooders than for the working classes, which continued to embrace bawdier morals. (Poor people did want better housing, just not necessarily for the same reasons that reformers saw it as desirable.)
But it's a nice little irony that the birth of privacy, which initially cast sex as something to hide from the world, actually created a space where sex could ultimately become less furtive. Sexual variety needs time and space to flourish, and those buttoned-down reformers inadvertently created just that.
The consequences of privacy for female pleasure are particularly profound, since "fast and furtive" just doesn’t cut it for most of us women, most of the time. In addition, young women had more sexual autonomy when they didn't have to fend off the advances of a tenant; the reformers were right that such tenants could pose a threat to women's bodily integrity. So even if the reformers were interested in protecting women's purity, in the end they did much more to facilitate women's sexual self-determination.
I'm still left wondering how people cope in Tokyo or Moscow, as figleaf asks. Many of them still live in conditions similar to early-twentieth-century crowding, with whole families in a single room, but they're subject to modern ideas about privacy and sexual propriety. I'd be very curious to know how they manage the resulting clash.