People Slept A Certain Way For Thousands Of Years—Then Habits Shifted, Globally

At least for millennia, the idea of attaining a full night’s sleep wasn’t innate. Nay, slumbers were divided into two shifts—a habit that was practiced pretty much globally until it disappeared, as historian Roger Ekirch found out during his research in the 1990s.

Ekirch was writing a book about the history of night-time, and he really wasn’t looking forward to working on the chapter on sleep. The topic sounded like a total snoozefest, and he believed sleep patterns were a biological constant, as Zaria Gorvett details in an intriguing BBC Future feature.

Nevertheless, he powered through, starting with a criminal deposition from 1699 detailing the testimony of nine-year-old Jane Rowth. In her telling, the girl described two men who had arrived at her window at about 11pm, instructing her mother to step out and follow them.

“Lye still, and shee would come againe in the morning,” Mrs Rowth whispered to her daughter, and left with the men. She never returned; her body was found days later. The woman’s brutal murder remained a mystery.

What particularly startled Ekirch, though, was Jane’s account of the time the two men were outside the house. Their arrival had awoken the mother and daughter from their “first sleep,” stated like it was a run-of-the-mill occurrence, “as though it was utterly normal,” said the historian.

In the months that followed, he’d stumble upon countless other casual mentions of the first and second sleeps. There was a deposition of Luke Atkinson of the East Riding of Yorkshire, who’d murder somebody or commit another crime in the window between both slumbers. Diaries, letters, newspaper articles, plays, and more all referenced the habit of double-sleeping.

In France, the first sleep was called the “premier somme.” In Italy, the term was “primo sonno.” Beyond Europe, there were mentions of this phenomenon in written records spanning Africa, Australia, the Middle East, South America, and South and Southeast Asia.

It appeared that people would turn in for their first sleep at between 9pm to 11pm. They’d rest for around two hours before awakening into the next phase: “the watch.”

These twilight hours served as a period of productivity—people would utilize them to get work done. The calm that moonlight brought in also made “the watch” the perfect time to chat in bed or even copulate. This window, too, would last a couple of hours before the next rest.

The “morning” sleep would be a prolonged one, stretching into the hours we’d usually wake up at today. And for the rest of the day, people would be up.

So, what changed in the following centuries? Ekirch believes the advent of artificial lighting is responsible for the shift—as environments got brighter, nights appeared shorter. “In addition to altering people’s circadian rhythms, artificial illumination also naturally allowed people to stay up later,” he described.

Biphasic sleep, as he’d later coin it, vanished by the end of the 20th century.

“The Industrial Revolution hadn’t just changed our technology, but our biology, too,” notes BBC Future’s Zaria Gorvett.

[via BBC Future, cover photo 174614065 © Pix569 | Dreamstime.com]