How Did We Sleep in Medieval Times? The Forgotten Practice of 'Two Sleeps'.

Since giving up my nursing career, where I was working daily 14 hour shifts, and switching to freelance research I have noticed a bit of a shift in my sleep pattern. I find I’ll often head to bed around 10-11pm and fall asleep fairly quickly, but then I’ll wake naturally at around 2-3am and often won’t drop off back to sleep again until 4 or 5.

I used to be a little concerned about this ‘disturbed’ sleep but as time went on I realised it doesn’t actually impact my life in anyway. Gone are the days where I have to be up by 5am so I can be ready to start my shift at 7, and in actual fact, even after not sleeping right the way through the night I find I’m normally still out of bed by 8am the next morning feeling quite rested.

Many of you reading this will be familiar with such a sleep pattern I’m sure, and may even be concerned about it and have gone seeking help or medical treatment for your apparent ‘insomnia’.

With experts recommending that humans require 8-9 hours of solid sleep every night, you could be forgiven for thinking that this is the norm.

But it hasn’t always been that way and in actual fact a biphasic sleep pattern or ‘two sleeps’ was normal practice for millennia until the

19^th century came along with its Industrial Revolution and artificial lighting, messing up people’s circadian rhythms!

For example in the 17th century a typical night time routine would entail a person settling down for their first sleep anywhere between 9pm-11pm, then a couple of hours later they would rouse and enter

‘a period of wakefulness’ also known as ‘the watch’. You have to remember too that the alarm clock wouldn’t be invented until the late 1700s so this habit of falling asleep then waking up again after a couple of hours was completely natural to people.

The wakefulness period could last anywhere between 1-3 hours and during this time, people would engage in similar activities to what they would do during the day, such as cooking, mending, checking on livestock or even attending church services. It was also an opportunity for married couples to spend quality time together as the initial sleep would take the edge off their exhaustion.

So if you’ve ever wondered how people back then had the energy to conceive so many children.. well now you know!

Biphasic sleep wasn’t just limited to England, it was widely practiced across the globe. The French referred to it as ‘premier somme’ and in Italy it was ‘primo sommo’. There has also been evidence that it was practiced as far away as Africa, South and Southeast Asia, South America and the Middle East.

So when did this practice stop?

By the 19^th century artificial lighting started to become more prevalent with gas lighting being introduced in London in 1807 followed by electric lighting by the end of the century. For the first time people were able to stay up and even work later, long past sundown.

But despite going to bed later people still had to rise early leading to a deeper more ‘compressed’ sleep pattern. Gradually the first sleep was lengthened and the second shortened and over the course of the 19^th century the practice of ‘two sleeps’ began to phase out altogether.

By the end of the 20^th century our biology had altered to the point where this nocturnal pattern disappeared entirely. Or did it?

I’m sure I’m not the only person who sleeps in two parts and I’ve realised now that what I termed as an irregular sleep pattern or insomnia is actually biphasic sleep and perhaps freeing myself from the constraints of shift work and allowing myself to fall asleep and wake naturally, rather than relying on an alarm clock has allowed my body to shift back into a ‘normal’ sleeping pattern. Normal for the 17^th century anyway!

Certainly, studies have shown that when humans are deprived of artificial light for an extended period their sleeping pattern transforms and they naturally sleep not in one stretch but in two halves, with a 2-3 hour period of ‘wakefulness’ in between.

So it seems that biphasic sleep is still very much part of our biology, just heavily repressed by artificial lighting as well as work patterns and lifestyles.

by Sarah Smith