Though it's an alien concept to us today, references to two sleeps can be found as far back as the Old Testament and Homer's Odyssey, and, more recently, in Don Quixote and Charles Dickens's Barnaby Rudge. The period between the two wasn't always a solitary affair, with people gathering to talk, have sex or visit the neighbours. But, the introduction of affordable light sources – from candlelight to public oil lamps – blurred the distinction between daytime and night-time activities and sleep patterns soon followed.

With after dark traditionally being a time of natural and supernatural danger for mediaeval and early modern Europeans, honest, decent people were supposed to be at home then. However, exceptions overwhelmed the rule, with peasants, midwives, drunkards, students and street-cleaners often out at night. It was the Parisian nobles and courtiers of the 1630s and 1640s who were the first to popularise the concept of expanding one's activities into the night as a sign of wealth, prestige and exclusivity – beginning the modern pattern of compressed sleep with one block of rest from about midnight until about 8am. Craig Koslofsky, associate professor of history at the University of Illinois, explores this in his new book, Evening's Empire: A History of the Night in Early Modern Europe.

"The social and cultural factors that reshaped sleeping patterns are called nocturnalisation," Kofolsky told me. "Nocturnalisation, defined as the increasing social and symbolic uses of the night, began to reshape sleeping habits, meal times, and all other structures of daily life beginning around 1650. Just as some Europeans at this time sought wealth, prestige, and power through colonisation of space, so too Europeans began to colonise the night, expanding their daytime activities into the night while developing new uses for lighting and darkness and leading to a compression of the first and second sleep into one block."

Over the course of the next 250 years the trend filtered throughout the rest of Western society and by 1920 the concept of the first and second sleep had been eradicated from our collective memory. Sleep scientists today are only just starting to unpack the evolutionary underpinning of insomnia and other prevalent disorders.

"There are some people who have adapted to modern society and are able to have this consolidated single sleep and there are others who have struggled to adapt as well and are easily distracted by noise and other disturbances and wake up in the middle of the night," explained Ron Grunstein, professor of sleep medicine at the University of Sydney.