[intro music] (host) Why do kids have Well, if you combine Victorian modesty, the rise of standardized clocks, and the spread of cheap suburban housing, you might end up with your own room.

"Go to your room" is a pretty big staple of American childhood, and many children who grew up with their own bedrooms remember them fondly as playrooms, places to build forts, sleepover kingdoms, the place where the Tooth Fairy gave you cold, hard cash, and also the place they were sent when they didn't play nice.

But whether you grew up with your own room or sharing with siblings, parents, and other family members, a bedroom's primary function is sleep.

For centuries, the luxury of having children in one room or a room with each child while parents slept soundly in their own master suite wasn't the norm for most people around the world.

In fact, it's still not accessible for many people in many places, considering the cost of having a large, multi-room house.

But it's not just about wealth because, even if a house has multiple rooms, there's no mandate on how we organize them, or choosing to create separate spaces for living and sleeping hours.

And the idea that children should sleep separately from parents at all was a concerted effort of colonial governments and early public-health advocates to discourage communal sleep.

There was nothing natural or inherent about it.

So, to understand where the idea of separate sleeping quarters emerged, first we have to ask: What were the norms for sleeping arrangements before kids had their own rooms?

Well, according to Benjamin Reiss in his book, "Wild Nights: How Taming Sleep Created Our Restless World," a lot of our images of "normal sleep" didn't exist before the 1800s in the West and the U.S. And a lot of that has to do with the developments of clocks and the importance of industrialized and regulated time.

For example, today, most people in the West and in the U.S. think of sleep in a relatively uniform way.

We're told that to encourage "healthy sleep patterns," we should prepare for bed at the same clock time every day throughout the whole year and sleep for eight hours, with adults in separate compartments from children.

And these compartments should be sealed off from the main living rooms of the house.

But Reiss argues that, prior to 1800, communal sleeping was relatively common around the world.

In Europe, until the 19th century and the Industrial Era, only the very wealthy had sufficient money to afford separate sleeping quarters for various members of the family.

And prior to industrialization, people's sleep schedules were often dictated by seasonal changes in daylight hours and the demands of agricultural work, more so than very regulated and consistent factory labor.

And according to historian Sasha Handley, throughout the 18th century in Europe, most rooms had several functions throughout the day and weren't reserved primarily for sleep.

And even amongst the wealthy, beds and bedding were very expensive, meaning that many households weren't overflowing with multiple beds, causing a certain amount of sharing between siblings, servants, and heads of household.

And in households where the heating was scarce or non-existent, communal sleep was an important way to ward off the cold.

Travelers on the road in Europe often shared beds with complete strangers overnight.

But sleeping is not just about wealth or the function of staying warm; it's also a cultural practice.

The Asabano people of Papua New Guinea extend communal sleeping to guests as a form of hospitality.

The Maori ended funerals of loved ones with communal sleep that involved the entire family.

And sleeping communally could also be a matter of safety and protection to ward off unwanted sexual advances or to remain safe from potential threats.

So, that brings us to our next question: When did the West start seeing solitary sleep portrayed as the most "natural" form of sleeping?

Well, that seems to be a combination of Victorian mores, colonial instruction, concerns about morality, and the spread of normative ideas about middle-class families in the West.

The first piece of this puzzle was a fear in Europe that sharing beds with strangers and travelers, and not just family members, could cause the spread of disease.

And these fears were documented as early as the 17th century and had some merit, especially in instances where communal sleeping was involuntary and practiced enforcedly unsafe conditions.

For example, European slave traders noticed a high rate of disease amongst white crew members and enslaved laborers who were tightly packed into dismal sleeping quarters of ships, causing the spread of dysentery and a high rate of mortality.

By the 19th century, the rapid spread of industrialization in the U.S. and Europe caused another fearful spread of disease in overcrowded lodging houses shared by factory workers, caused in part by cramped living quarters and a dangerous lack of ventilation.

There was a fear that certain diseases, like cholera, could be spread through the air, although this was later debunked since the spread of cholera was linked to unclean drinking water.

But the fear of these unhygienic boarding houses was coupled with the fear that the close communal sleeping of poor workers also led to "immorality."

And in 1851, British Parliament passed the Common Houses Lodging Act to raise the standards of these boarding houses, and privacy was a basic component of this new law.

By the end of the 19th century, fears that communal sleeping was both unhealthy and a marker of sexual immorality had physicians and public officials looking to enforce solitary sleep, both in the U.S., Europe, and also in countries that fell under colonial rule.

Single bedrooms and solitary beds began to be pushed as a marker of "civilization," and people who engaged in group sleep were portrayed as "savage" and undeveloped.

Representations of communal sleep were marked by racism that proposed that those who slept in shared quarters were animalistic, while those who slept separately were more civilized, which leads us to our final question: Why did this practice continue into the 20th century?

This belief was reinforced in the 20th century with the spread of suburban developments in the U.S. Middle-class ideals of suburban sprawl were marketed specifically to white families where homes were sectioned off into separate rooms with each room serving a specific function, including the bedroom.

Now families who were not extraordinarily wealthy could also maintain sectioned-off rooms reserved entirely for sleep.

Hence, kids were shown sequestered in rooms only with other children or entirely alone from an early age.

This even included sleeping separately in individual twin beds, which was sometimes portrayed as "healthier" for children or even married couples, although not always practiced.

But Sears and other department stores continued to advertise sitcom- style individual twin beds for married couples into the 1960s.

So, how does it all add up?

Well, the concerns of rapid industrialization, overcrowding in European and U.S. cities, and the high mortality rates of enslaved persons forced into ships, combined with Victorian culture's desire to label communal sleeping amongst poor workers as sexually immoral and irregular, led to the spread of separate sleeping conditions becoming more regularized in the 19th century.

So, there are very specific situations in which communal sleep and overcrowding were shown to be a hazard to workers and people living in dangerous conditions.

However, the idea of a large home where it's possible for all members to sleep in sectioned-off quarters isn't always ideal or achievable.

Large homes with private rooms require money to heat and maintain, as well as require sizeable incomes to purchase in the first place.

So, not every family can afford the luxury of sectioned-off quarters or individualized bedrooms.

And despite the representation of communal sleep as an oddity after the rise of colonization, it still remains in practice today.

And now we think of communal sleep as pretty much only normal between young children and siblings or romantic couples.

But fully separate sleep may have some unintended health benefits.

Dr. Colleen Carney, director of Ryerson's Sleep and Depression Laboratory, found that as many as 30 to 40% of couples sleep in separate beds, and report that sleeping apart offers a more restful night.

So, for some, communal sleep is a survival necessity and a common cultural practice, whereas for others, it's the difference between a good night's sleep and some time spent tossing and turning.

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