Humans Used to Sleep Twice Every Night -- What Happened?

Tuesday, November 04, 2025

Continuous sleep is a modern habit, not an evolutionary constant, which helps explain why many of us still wake at 3 am and wonder if something's wrong. It might help to know that this is a deeply human experience.

Posted by lamplighter at 11:30 PM | 15 COMMENTS | permalink | Comment on This Entry |

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... For most of human history, a continuous eight-hour snooze was not the norm. Instead, people commonly slept in two shifts each night, often called a "first sleep" and "second sleep."

Each of these sleeps lasted several hours, separated by a gap of wakefulness for an hour or more in the middle of the night.

Historical records from Europe, Africa, Asia, and beyond describe how, after nightfall, families would go to bed early, then wake around midnight for a while before returning to sleep until dawn.

Breaking the night into two parts probably changed how time felt. The quiet interval gave nights a clear middle, which can make long winter evenings feel less continuous and easier to manage.

The midnight interval was not dead time; it was noticed time, which shapes how long nights are experienced. ...

#1 | Posted by LampLighter at 2025-11-03 09:02 PM | Reply

Interesting ...

Pop the phrase "wide awake at 3am" into your search engine of choice.

#2 | Posted by LampLighter at 2025-11-03 09:07 PM | Reply

I've always slept like that, and it's why I've never had a problem with insomnia. I expect to sleep in "shifts". I love the middle awake part of my sleep cycle. It improves my dreams too.

#3 | Posted by RightisTrite at 2025-11-05 02:15 AM | Reply

Interesting piece.
That two-sleep night reflected a different.p existence.
Causes me wonder whether the diminishing of night affects the telling of the old constellation stories.
Is there space anymore for them in modcon societies?
You gain, but in acquiring you also divest.

#4 | Posted by Doc_Sarvis at 2025-11-05 05:08 AM | Reply

#4: Morning Doc Sarvis: If you recall from Shakespeare's Henry V , in Act IV Prince Hal walks around at night incognito and mingles with the English soldiers before an imminent battle. They are all up and sitting around campfires.

Seemed that in antiquity people ate and retired at dusk. Waking up in a few hours, they would light candles or torches, see other lights about, and commune again with their neighbors before retiring again. Funerals were also held at night many, many years ago.
The Mediterranean and Latin 'siesta' breaks up the day into two sleep cycles as well.

Indoor lighting (gas, than electricity) probably changed our sleep pattern by extending the social day a few hours past dusk.

"Yawn! What time is it, dear?"

"Almost midnight, honey."

"Well, I'm off to bed then. Zzzzz."

#5 | Posted by C0RI0LANUS at 2025-11-05 05:32 AM | Reply

Working night shifts and graveyard shifts nearly destroyed my internal clock. Took years to recover.

Now I am retired. So now I get to sleep when my body tells me it's time to rest.

Not a clock.

And other humans don't get to tell me when I'm tired either. The sun doesn't tell me when I'm tired. My body does. And now finally I can take the time to actually listen to it.

#6 | Posted by donnerboy at 2025-11-05 09:25 AM | Reply

For as long as I can remember I wake up almost exactly 8 hours after I fall asleep.

#7 | Posted by AMERICANUNITY at 2025-11-05 10:07 AM | Reply

Seems to me that sleeping light and waking up every so often would be a very good survival strategy when you sleep in caves and there are giant cave bears, saber tooth tigers giant sloths roaming about just outside.

#8 | Posted by donnerboy at 2025-11-05 11:26 AM | Reply

@#6 ... Working night shifts and graveyard shifts nearly destroyed my internal clock. Took years to recover. ...

Same here.

... Now I am retired. So now I get to sleep when my body tells me it's time to rest. ...

Similar here. However, I do notice the middle of the night wakeup.

#9 | Posted by LampLighter at 2025-11-05 01:58 PM | Reply

People used to sleep sitting up, too.

#10 | Posted by LegallyYourDead at 2025-11-05 03:20 PM | Reply

People used to sleep sitting up, too.

#10 | Posted by LegallyYourDead at 2025-11-05 03:20 PM | Reply | Flag: Dummkopf Trumpf Still Does

#11 | Posted by C0RI0LANUS at 2025-11-05 03:32 PM | Reply | Funny: 1

@#10 ... People used to sleep sitting up, too. ...

My Mom used to sleep in her living room chair at times.

#12 | Posted by LampLighter at 2025-11-06 12:54 AM | Reply

Kudos for posting this, Lamp. Interesting stuff, and I wonder how many will rethink how they've been living and doing they're work after realizing that maybe we're not wired for the traditional

#13 | Posted by hamburglar at 2025-11-06 05:00 AM | Reply

I'm a long-time devotee oof the Garmin Fenix series of watches, which do a pretty good job of tracking sleep patterns. It's far more common than not for me to wake up at 3am and be very awake. By 5am I tend to drift back off to sleep. My watch tells me I get my best sleep between 5am and 7am.

I used to get up and go to the gym around 4am, but now I prefer the sleep.

#14 | Posted by madbomber at 2025-11-06 01:47 PM | Reply

My personal sleep pattern is thus:
1:30-2:30 AM go to bed (McWife went down at midnight), I roll out of bed to hit the bathroom at about 8:00 AM, then frequently shower, sometimes shave, etc. Usually, there's NOTHING on my personal event horizon, so I'll "surf" the Internet for news, current events, and comics. "Bloom County" is Back! After about three to four hours of mindless "surfing," I'll try to find something interesting on Netflix. I seek out stuff labeled "TV-MA violence, nudity, sex, drug use, smoking, self-harm, firearms, etc." There's a subset of Channel 26, channel 26-3, AKA "Grit." Cowboy movies 24-7! "High Plains Drifter" was on last weekend.

#15 | Posted by john47 at 2025-11-06 03:53 PM | Reply