Christine Baumgarthuber of the delightful Austerity Kitchen blog has a column on how people slept in pre-industrial societies. Instead of a single eight-hour interval, most people had a “first” and “second” sleep:
The idea of first and second sleep derives from a form of life that disappeared with the onset of industrialism. Until the close of the early modern era, writes Roger Ekirch in At Days Close: Night in Times Past (2005), Western Europeans on most evenings experienced two major intervals of sleep bridged by up to an hour or more of quiet wakefulness. When an individual took her first sleep depended, like it does today, on disposition and life circumstances. Most, however, went to bed with the sun. Chaucers Squires Tale mentions that Canacee slept soon after evening fell and awoke again during the early hours of the morning. The thirteenth-century Catalan philosopher Ramón Lull characterizes first sleep as stretching from mid-evening to early morning, while the French writer Noel Taillepied maintains that it is about midnight when a person wakes from it.
My first reaction to this is mild disappointment. I’ve long been impressed at stories of the monks and nuns of medieval Europe rising in dead of night to pray matins and lauds. It would seem they were much more conventional, and less austere, than I had supposed.