Being your slave what should I do but tend
Upon the hours, and times of your desire?
I have no precious time at all to spend;
Nor services to do, till you require.
Nor dare I chide the world without end hour,
Whilst I, my sovereign, watch the clock for you,
Nor think the bitterness of absence sour,
When you have bid your servant once adieu;
Nor dare I question with my jealous thought
Where you may be, or your affairs suppose,
But, like a sad slave, stay and think of nought
Save, where you are, how happy you make those.
So true a fool is love, that in your will,
Though you do anything, he thinks no ill.
The longing stems in this case from desire and vulnerability brought about by feelings of love and adoration. It was not generally thought a good thing in Shakespeare's time that love should be requited. The most violent affections were considered suspect - they tended to distract one from the practice of religion and one's social obligations. Making a socially acceptable match and being married according to law and custom was the only credible option. If the match happened to also bring affection and desire, one counted oneself as fortunate.
Indeed the institution of marriage was just one of many social constructions which had the effect of repressing sexual urges and channeling them into proper behaviors. In the Christian dogma of the late medieval and early modern eras, the body was perceived as evil, particularly the female body, and any pleasure irredeemably perverse. However, under the Catholic and Lutheran strains of Christianity we are all sinners, required to repent and beg mercy from our Lord. It was the scamp Calvin who championed perfection through self-denial, including denial of any pleasure whatsoever in the act of conceiving the children we are obligated to produce.
Still, unusual pleasures were considered worse than typical ones. Sodomy was socially unacceptable in the extreme, even though many married folks probably practiced it in secret. It was useful as a political tool for targeting one's enemies, so the Catholic church labeled it a heresy which gave them a justification for executing those found guilty.
But back to the topic of sexual repression. Scourging and other forms of penitence were used to repress sexual urges. Foucault writes eloquently about the practice of confession and how it transforms deeds into words which are then categorized and neutralized, thus producing a very effective form of social control.
At the same time, social hierarchy was the order of the day and virtually everyone was engaged in some form of Master/slave dynamic. Men dominated women, Lords dominated lesser nobility and commoners, Landlords dominated tenants, Lords, ladies and anyone who owned property dominated servants, Royalty dominated everyone and the Church dominated the parishioners, not to mention Masters who actually owned slaves. Anyone seeking to learn a trade entered into an apprenticeship with a Master, an arrangement that seems to have been borrowed heavily by the "Old Guard" leathermen of the 20th century. There is no doubt in my mind that Masters and Mistresses of all stripes in this social hierarchy elicited sexual services from underlings.
My theory, then, is that those practices that either in intent or effect repressed sexuality became fetishized. The French Libertines, with our namesake De Sade in the forefront, seized on this and developed it into an art form. Rather than finding pleasure in the thing itself they transferred no small portion of that pleasure to the act of transgression. De Sade's writings do not closely resemble kink as it is practiced today, but instead focus on the most transgressive acts possible, such as rape, bestiality and necrophilia.
The Victorian era, again with a debt to Foucault, brought an orgy of social control. Institutions sprang up like weeds and all of them carried the mandate of observing, cataloging, categorizing and disciplining the body politic. Hospitals, Prisons, Schools, Orphanages, and Poorhouses were established to contain social ills against the rising tide of personal liberty engendered by industrialization and capitalist wage labor. Schools used corporal punishment to keep students manageable, and their moral behavior was considered just as important as their studies. Children caught masturbating were severely punished. People who exhibited sexual license could be treated in hospitals and asylums for their "disorder".
Ultimately, both the methods of control and the control itself were entwined with our sexual makeup. While only a small fraction of us practice kink openly or secretly (let's say for the sake of argument that there are 3 million kinksters nationwide - that's still only 1 percent) the cultural tropes we trade in are incorporated into the vanilla sex industry, e.g., the naughty nurse, french maid, schoolgirl, farmer's daughter, cop, bunny, cat, barmaid and pirate wench are all featured in vanilla porn and stripper acts, and can be purchased as sexy lingerie.
All of this transformation from mode of repression to mode of sexual expression was facilitated by a much larger transition from scarcity to abundance. Some time around the introduction of mass production, we acquired the ability to produce far more goods than we need, and so the emphasis in society shifted from producing a disciplined workforce to consuming. Consumption is encouraged by license - go ahead, treat yourself, you deserve it. And sex is not left out of the equation. While much marketing sneaks the product in as a replacement for actual sex, the desire for sex is presumed to be constant, intense and unstoppable. This age of expression was drafted in part by Freud whose most influential idea was that the repression of healthy sexual urges results in strange behaviors and physical illnesses, the cure for which is to find the root cause of the urges and direct them into healthy, mature behavior. (According to Freud vaginal intercourse was of course healthy and mature).
Hence, we are a nation of repressed people who have been told to want sex all the time. Rather than being surprised that a few people might be kinky, I'm more surprised that our numbers are still relatively small. D/s lifestyles trace their roots back to real-life power relations. The interrogation scene draws on a fetishization of police and military force but also goes back to the Catholic sacrament of confession. Caning, flogging and whipping were all used as real forms of corporal punishment in numerous social institutions. Bondage was used for various purposes going back to ancient times, while the "damsel in distress" trope became prominent as women's sexuality was repressed to the point that it was considered not to exist at all. Women who were told that they did not possess a sexuality channeled their desires into fantasies about being abducted, tied to the tracks, raped, ravished and seduced, as these all removed the woman's volition from the equation.
There are a lot of people running around the kink community who say that it is unnatural for us to attempt to have egalitarian societies and that Dominance and submission will eventually resurface. I don't know exactly what to make of this idea, as I tend to believe in the democratic ideal of political equality - that it is the responsibility of a just government to ensure that all citizens are equal under the law and have equal opportunity to participate in their political system. That is to say, even though I submit to Dr. Faust, in theory he has no greater privilege under the law and can be held to exactly the same code of conduct as I am. Indeed, I would not want to be unequal in the eyes of the law. I enjoy voting, owning property and engaging in productive, fairly compensated labor on a voluntary basis. All of which contributes to my ability to take care of myself and enter and leave social relationships at my own discretion, hence the traditional D/s relationship engaged in by men and women is disrupted and men are no longer presumed to own their wives. The fact that I and my kinky brethren desire dominance and submission does not negate the political desirability of justice under the law, no matter how persistent the human urge to conquer, control and exploit seems to be. Indeed, it is precisely the seemingly unstoppable ferocity of this urge that necessitates justice.