Apparently, sleeping eight hours straight in a row is a fairly recent development. As recently as a century ago, people slept in two four-hour chunks:
In the early 1990s, psychiatrist Thomas Wehr conducted an experiment in which a group of people were plunged into darkness for 14 hours every day for a month. It took some time for their sleep to regulate but by the fourth week the subjects settled into a very distinct sleeping pattern.
They slept first for four hours, then woke for one or two hours before falling into a second four-hour sleep.
Sounds like something that happens only in the lab, right? Well apparently, there are hundreds of references to this "segmented sleeping patterns" in the historical record. According to the BBC, "these references describe a first sleep which began about two hours after dusk, followed by waking period of one or two hours and then a second sleep."
What did people do during this "waking period"?
[T]hese hours weren't entirely solitary - people often chatted to bed-fellows or had sex. A doctor's manual from 16th Century France even advised couples that the best time to conceive was not at the end of a long day's labour but "after the first sleep", when "they have more enjoyment" and "do it better".
So basically, a century ago people would sleep for 4 hours, laze around for 1-2 hours while they chatted and had sex, and then sleep for 4 more hours? The 16th Century sounds awesome! Well, except for constant war and famine, high infant mortality, racism, sexism, slavery and the plague.
What is your sleep cycle like... do you take all of your sleep in one go, like a 20th/21st Century type? Or do you break it into two chunks like a true Renaissance Woman?