For the urban workforce of the Soviet Union, September 29, 1929, was a Sunday like any other—a day of rest after six days of labor. Sunday was the prize at the finish line: a day’s holiday, where people might see family, attend church or clean their homes.

But in the eyes of the Soviet government led by Joseph Stalin, Sundays represented a genuine threat to the whirr and hum of industrial progress. For one day in seven, after all, machines sat silent, productivity slumped to zero and people retreated to comforts thought to be contrary to the revolutionary ideal, like family life or religious practice.

On the following Sunday, no such collective pause for breath took place. Eighty percent of the workforce were told to go to work; 20 percent to stay home. The ordinary seven-day week now had a new bedfellow: the nepreryvka, or “continuous working week.” It was five days long, with days of rest staggered across the week. Now, the Soviet economist and politician Yuri Larin proposed, the machines need never be idle.

The nepreryvka was supposed to revolutionize the concept of labor, set a match to productivity and make religious worship too troublesome to be worth the effort. But it failed on virtually every count. Adjustments were made and in 1931, the cycle was extended to last six days. After 11 years of trial and error, the project was axed in June, 1940.

Unlike the ordinary seven-day week, the continuous week began as a five-day cycle, with each day color-coded and marked with a symbol. The population would be carved up into as many groups, each with its own rest day. The days of the week, as familiar as family members, would gradually be stripped of meaning. Instead, each of the five new days was marked by a symbolic, politically appropriate item: wheatsheaf; red star; hammer and sickle; book; and, finally, budenovka, or woolen military cap.

Calendars from the time show the days marked out in colored circles like beads on a string: yellow, peach, red, purple, green. These circles indicated when you worked and when you rested. This was shift work, on the most enormous scale in human history.

Yet from the very beginning, there were rumblings of dissent from workers. Letters published in Pravda, the official newspaper of the Communist Party, complained that staggered rest days defeated the purpose of time off: “What is there for us to do at home if our wives are in the factory, our children at school and nobody can visit us? It is no holiday if you have to have it alone.” Another griped: “How are we to work now, if mother is free on one day, father on another, brother on a third and I myself on a fourth?”

The ostensible reasons for the shift were economic. Its accidental social consequences, like families being unable to come together, or religious practice made more challenging, seem to have been seen as a bonus. In one diary entry dated shortly before the changeover, the historian Ivan Ivanovich Shitz wrote disparagingly about how the nepreryvkawould kill off Sundays and all Christian holidays, he wrote, and make it impossible for people to meet in groups, whether union-based or political, or as a family.

Finally, he wrote, its primary function seemed simply to generate the illusion of a culture of intense work. There are few actual accounts of the family problems the continuous week likely caused. It became common, however, for people to color-code their friends and acquaintances in their address books according to which day they had off.

It’s quite possible, argues Eviatar Zerubavel, sociologist and author of The Seven Day Circle: The History and Meaning of the Week, that the calendar reform tied into a traditional Marxist aversion toward the family. Making family units less integrated may even have been a conscious part of the agenda.

In the absence of technology, Zerubavel says, temporal symmetry—“that your schedule and my schedule are in sync, that we are at work at the same time and off at the same time”—is the glue that holds society together. “Here, there was no common rest.” Without it, it was easier for Soviet powers to divide and conquer.

Eventually, measures were introduced to make it easier for families to sync up, largely due to complaints from workers. In March, 1930, the government began recognizing families’ requests for simultaneous days off—the first of many minor reforms that attempted to make the nepreryvka a functional experiment.

It seems more likely that the nepreryvka was trying to attack the week’s religious cadence. If the Soviet government had been concerned merely with economic waste, it would have been easy enough to maintain the seven-day week and stagger rest days across that time. (The five-day cycle did, after all, mean that people were getting over 70 weekly days off a year, rather than than the 52 they had had before.)

Instead, it was hoped that as the nepreryvka, and its six-day successor,took hold, the traditional weekdays would fade out and with it, their whiff of religiosity. As Tony Wood, author of Chechnya: The Case for Independence notes, “The Russian for Saturday is Subbota, from ‘Sabbath,’ while the word for Sunday is simply ‘Resurrection.’”

The continuous week, the theory went, would make religious adherence near-impossible. Without a Friday, Saturday or Sunday, Muslims, Jews and Orthodox Christians alike would not be able to attend services, and that was considered a winning outcome, two years into the Soviet government’s campaign against religion.

Innovations that might break the hold of religion on people’s minds, therefore, were met with enthusiasm. It may seem ludicrous that making religion more inconvenient could be believed to stamp it out, Wood says, “but you have to bear in mind that no one had ever tried this, so no one knew how it worked.”

Even if these and other restrictions didn’t minimize people’s faith, industrial secularization may have had a lasting impact on religious adherence, he says. “I think it did make a difference.” Modern Russians often say they’re religious, but have in recent history been far less likely to attend church than their counterparts in Western Europe or the United States.

The were whole swathes of the population outside of urban centers who remained virtually untouched by the continuous week or more general attempts at calendar reform. In rural areas, farmers might spend their days waiting for things to grow, taking care of animals, or harvesting crops, says Wood, and not engaged in anything that could easily be turned into staggered shifts.

“The working rhythm is already very different.” Far away from the country’s bureaucratic urban centers, agrarian life went on much as it had before—though many peasants made a point of taking off both new, secular state holidays and traditional days of worship. In 1931, says the historian Malte Rolf, author of Soviet Mass Festivals, “almost all officials were complaining about the still existing ties of rural people to ‘traditional habits,’” where their physical separation allowed them distance from the Soviet overhaul taking place in cities.

It’s hard to know precisely the legacy of the continuous week: it was, after all, just one part of the enormous cultural and political overhaul caused by Soviet industrialization. But it might be most apparent here, in the split between urban and rural life, with each running on a slightly different rhythm.

This divide is alluded to in the 1931 novel, The Golden Calf, where the continuous week turns a character’s “good clean Sundays into some kind of violet ‘fifth days.’” In disgust, he “escapes the regime,” and opts to leaves the city. Around the same time, internal passports were introduced to control how many peasants could migrate into the cities and leave the terrible conditions associated with farming. A version of this is still in place today in Moscow, ostensibly to limit how many people can move to the city.

For that 11-year period, calendars across the Soviet Union must have been anarchic—public transport running on a five-day cycle, many workplaces on six, the stubborn rural populace on the traditional seven. In the end, however, it failed on both its stated and presumed goals, and productivity actually fell. Constant use proved damaging for the machines. As early as 1931, it became clear that so-called shared responsibilities often meant no one taking ownership of their work tasks, to deleterious effect.

On June 26, 1940, a Wednesday, a Decree of the Presidium of the Supreme Soviet declared the seven-day cycle reinstated. But though Sundays were holidays once again, they came at a different cost: For ordinary workers, quitting one’s job, missing a day’s work or being over 20 minutes late became criminal offenses, with mandatory prison sentences. The nepreryvka had been tossed aside, but the ideologies that inspired it remained intact.