Your 'Broken' Sleep Isn't Broken — Civil War Soldiers Knew Something We've Forgotten

You wake up at 2:47 a.m. The room is dark, your phone says you've only been asleep for four hours, and your brain immediately starts catastrophizing about how exhausted you're going to be tomorrow. You scroll. You stress. You finally drift off an hour later feeling like your body has failed you.

But what if it hasn't?

What if that midnight wakefulness isn't insomnia — but an ancient, functional sleep pattern that humans relied on for centuries, that soldiers used to survive brutal campaigns, and that modern sleep researchers have quietly started calling one of the most natural rhythms the human brain produces?

Welcome to biphasic sleep. Most Americans have never heard the term. But their great-great-grandparents almost certainly lived by it.

Two Sleeps Were the Norm, Not the Exception

Before gas lamps, before electric light, before the Industrial Revolution reshaped the American workday, people across the world didn't sleep in one long uninterrupted block. They slept in two. Historian Roger Ekirch spent over two decades combing through diaries, court records, medical texts, and literature from the pre-industrial era, and what he found was stunning: references to a "first sleep" and a "second sleep" appeared everywhere, treated as completely ordinary.

People would go to bed around dusk, sleep for three to four hours, wake naturally for an hour or two — sometimes to pray, talk with a spouse, tend to animals, or simply lie quietly — and then drift back into a second, lighter sleep until morning.

This wasn't just a European habit. Accounts from American history document the same pattern among Civil War soldiers, who often broke their limited rest into two windows during long campaigns. Sailors on overnight watches built their entire rotation around it. Rural laborers across the American South and Midwest treated middle-of-the-night wakefulness as unremarkable — useful time, not lost time.

The single-block "monophasic" sleep we now consider normal? That only became the standard after the Industrial Revolution forced workers onto rigid schedules and artificial light made it possible to push the first sleep later and later into the night — eventually squeezing both sleeps into one compressed window.

What Actually Happens in That Midnight Gap

Here's where it gets genuinely interesting from a brain chemistry standpoint.

Sleep researchers studying biphasic patterns have found that the wakeful window between two sleep periods tends to fall during a natural trough in the body's sleep pressure cycle. Prolactin — a hormone associated with a calm, almost meditative mental state — spikes during this period. People who wake naturally during this window often report feeling unusually peaceful, even reflective, rather than groggy or anxious.

Some researchers believe this is precisely when the brain consolidates certain types of memory and emotional processing. The REM sleep that bookends both halves of a biphasic night appears richer and more complete than the REM produced in a single compressed block.

Psychiatrist Thomas Wehr at the National Institute of Mental Health ran a landmark experiment in the 1990s where he removed artificial light from participants' environments for weeks. Without fail, nearly every subject spontaneously shifted into a biphasic pattern — waking for one to two hours in the middle of the night, feeling calm and alert, then returning to sleep. Their bodies weren't malfunctioning. They were reverting to a default.

Why Nobody Told You This

So why does every sleep hygiene article, every doctor's pamphlet, and every mattress commercial insist on eight uninterrupted hours as the gold standard?

Partly, it's industrial legacy. The eight-hour sleep block emerged alongside the eight-hour workday — a neat, standardized unit that fit the factory schedule. Once that norm was established, any deviation from it became medicalized. Middle-of-the-night waking got a diagnosis: sleep maintenance insomnia. Pharmaceutical companies built entire product lines around treating it.

The irony is that what millions of Americans are being prescribed medication for might simply be their nervous system doing what nervous systems have done for most of human history.

That's not to say real insomnia doesn't exist — it absolutely does, and chronic sleep deprivation is genuinely dangerous. But the reflexive assumption that waking at 3 a.m. means something is broken deserves a serious second look.

What You Can Actually Do With This

You're probably not going to restructure your entire life around two sleep periods — modern schedules don't exactly accommodate a quiet hour of reflection at midnight. But understanding biphasic sleep offers something immediately useful: permission to stop panicking.

If you wake in the middle of the night, anxiety about being awake is almost certainly making things worse. The historical biphasic window was characterized by calm wakefulness, not dread. Try treating it that way. Don't reach for your phone. Don't start calculating how many hours you have left. Lie quietly. Read something non-stimulating. Let your prolactin do its thing.

Some sleep coaches and chronobiologists now suggest that people who struggle with monophasic sleep might actually be better served by leaning into a structured biphasic schedule — an earlier first sleep, a deliberate short wake window, and a second sleep — rather than fighting their biology with a sledgehammer of sleep aids.

The soldiers who marched through Virginia in 1863 didn't have melatonin gummies or white noise machines. They had two sleeps and a body that knew exactly what it was doing.

Maybe yours does too.