Days of the week: when did the current cycle begin?

I know that different languages use different names for the almost universal seven days of the week. I also know that not all peoples consider Monday, for instance, to be the first day of the week. My query is not about the names of the days (though feel free to drop in with interesting facts relating to same).
What I’m after is when did the unbroken line of …MonTueWedThuFriSatSunMonTueWedThuFriSatSunMonTue… start. And the related, has there been a documented restart analogous to the transition form Julian to Gregorian calendar?

I think the title of the topic asks it more clearly than the body, so just run with that.

It depends on what country you’re talking about. The Gregorian calendar was adopted by most of the western world in 1582. Because the older Julian Calendar didn’t account for the fact that a solar year is actually 365 and 1/4 days long the calendar had “drifted” almost 2 weeks putting Easter in the “wrong” spot. The Gregorian added the leap day counting proceedure and basically jumped 10 days ahead. The “Protestant” world (ie the English Empire) didnt adopt the calendar until 1752 so they had to jump 11 days ahead. Various other places adopted the calendar at a leisurely rate with Greece being the last in 1923.

As far as I’m aware, there is no recorded restart. The unbroken sequence goes back as far as there are records in any culture.

Most cultures also associate the sun, moon, and planets with the days of the week, and the associations are same.

The 11-day jump had no effect on the days of the week. The very Wikipedia article that mikecurits linked to says (very near the beginning) that:

Thursday 4 October 1582 was followed by Friday 15 October 1582.

yes, good point. I kinda made a hash of the original question. TokenRing even points out the Julian/Gregorian shift. . .so everyone should just ignore my answer.

Thanks @GreenWyvern (and @mikecurtis and @Keeve)
So “our” sequence goes back unbroken into the mists of time and so does all other cultures’ version of the same thing. The particular sequence we are on of seven named days with one named for the Sun succeeded by the one named for the Moon and so on got started by a proto-culture and has never been interrupted.
Other cultures had their own sequence (that may or not have had seven days and may or may not have had a sun-day followed by a moon-day). Those cultures either carried on doing what they were doing OR adopted the sequence we are on.

I was imagining that there were peoples in different geographic regions with a 7 day week cycle that were not synchronised and at some point became so. Just goes to show that there are no stupid questions but at least one stupid questioner!

TokenRing, “synchronized” might not be the right word, and other cultures definitely don’t necessary have “a sun-day followed by a moon-day”.

For example, as you wrote, “Sunday” is indeed named after the sun, but the Spanish “Domingo” comes from the Latin “Dominica”, referring to their lord. Similarly, “Wednesday” is named after the Norse god Odin, while in Spanish, “Miércoles” is named after the Roman god Mercury.

I think it would be more accurate to point out that for as long as English and Spanish have co-existed, Sunday has always been the same day as Domingo, and Wednesday has been the same day as Miercoles. In other words, regardless of what you call the name of the day, the same 7-day cycle has been going since before we started recording this stuff.

I think the Jews have been using a 7 day week for nigh onto 3 millennia. In Israel, the days of the week are named Day 1, Day 2,…, Day 6, Shabat. As far as I know they have maintained this unbroken cycle since it started and gradually most of the rest of the world adopted it giving the days whatever name they liked.

Older thread (started by my humble self) raising this very question: Are weekdays a sequence uninterrupted for millennia?

I’d also like to add that it’s a bit oversimplifying to say that the Gregorian calendar was adopted by most of the Western world in 1582. It was established by a papal bull and, accordingly, obeyed only by the Catholic countries initially - which meant a lot in these post-Reformation days. Protestants (England and its dependencies, Scandinavia, the Low Countries, much of Germany) ignored it, and so did Orthodox Christianity (which I think can be seen as part of the Western world). The absence of England, in particular, is the cause for one of my favourite quirks in all of human history, namely the fact that Shakespeare and Cervantes died on the same date (23 April 1616) yet ten days apart.

I don’t believe the seven day cycle was universal. Certain cultures used different week lengths. Ancient Rome, pre-Christianity, had an eight day week. The Igbo of Biafra used a four day week (every fourth day was “market day”, essentially a one-day weekend).

I think we use a seven day cycle because Jews used a seven day cycle, ending on Sabbath. (For Jews, Sabbath is Saturday, or more specifically Friday sunset to Saturday sunset.) I don’t know how long that cycle has gone on, but I suspect it has lasted since the construction of the Second Temple. Christianity carried this forward, eventually taking over Rome (and eliminating their eight-day week). Western influence has spread worldwide, to the point that we have consistent day numbering and western business suits are very common among high-status men. On a similar note, the Abrahamic religion Islam has a holy day, and that has been consistent with the week used in Judiaism and Christianity for at least twelve centuries.

The seven day cycle persisted regardless of which day is the first day in the week (Monday in some countries, Sunday in others) as it’s really a communication technology.

The most widely used calendar has been separated from its Roman and then Christian origins, but many places have a simultaneous “traditional” calendar covering folk/religious holidays and the like. I think Japan has one holiday celebrated on three separate days, depending on which calendar you are using. (That sounds confusing!)

Speaking of communication, different countries handle months differently. In Japan, people don’t use month names. January is merely “the first month”. As long as this can be communicated to someone from another country, it doesn’t matter that they’re not replicating a Roman month name (or any month name).

@Schnitte, yours was a much betterly phrased question. Thanks for the signpost.

Ancient Rome, pre-Christianity, had an eight day week.

And, confusingly, they called it a nine-day week (nundinae because the Ancients engaged in inclusive counting, according to which the first day of the subsequent week was the ninth day counting from the start of the preceding one.

Yea, that would be my Catholic bias showing through.
As I said…hash…I’m blaming the virus

Technically, the Hebrew names for the days of the week are the names the days are given in the Bible: First Day, Second Day, Third Day and so on - as in “On the first day, God created…” The names are usually abbreviated in writing as “Day A” through “Day F” (but with Hebrew letters, of course). Shabbat is Shabbat no matter what, without the “Day”, and is usually abbreviated as “S”

It depends on what country you’re talking about. The Gregorian calendar was adopted by most of the western world in 1582. Because the older Julian Calendar didn’t account for the fact that a solar year is actually 365 and 1/4 days long the calendar had “drifted” almost 2 weeks putting Easter in the “wrong” spot. The Gregorian added the leap day counting proceedure and basically jumped 10 days ahead.

The Julian Calendar (mostly) did account for this; it had leap years. (Any calendar that didn’t would have diverged much further and faster from the solar year.) What it didn’t have is the exception where years divisible by 100 are not leap years unless they are also divisible by 400.

Most likely the seven day week pre-dates written language by a good long time, so it’s really impossible to answer the OP. Small towns in the Middle East go back 10 or 11 thousand years, maybe more. Once towns were invented, there would be arise a need for a regular market day every few days. The early Mesopotamians seem to have had a 7-day week and it spread from there.

According to Wikipedia, the current 7-day cycle (not necessarily with the same names) goes back to at least the 6th century BCE and has its roots in Judaism, which may have itself been influenced by a Babylonian or Sumerian tradition, but without extra day’s thrown into the cycle to account for lunar phases.

Presumably, this would have then spread to other parts of the world via the Christian calendar and its roots in Judaism, at times helped along by the European drive for colonialism.

There doesn’t seem to be any logical reason for the seven-day week. A year is dictated by the time it takes for the earth to orbit the sun, a day is dictated by the rotation of the earth. A month is more or less related to the lunar cycle (about twenty-seven and a quarter days) although by that reckoning there should really be thirteen months in a year.

One authoritative source credits the seven-day week to the Babylonians whose study of the celestial bodies meant that the number seven had a particular significance. Of course, the Babylonians were responsible for the sixty minute hour and the 24-hour day as well. It was them who gave the Egyptians (who had a ten day week), the Persians, the Jews and the Greeks a seven-day week and thus spread the idea right across the world, through India and on to China.

Of course, it’s all down to trade. As soon as countries start trading with each other they need to have some common parameters and the dominant country will impose its own ideas on its weaker trading partners. In modern times it can be hard enough for people to deal with different time zones. Could you imagine trying to set up a meeting if Wednesday in California was Monday in New York and Thursday in London, all with different names and different dates?

There doesn’t seem to be any logical reason for the seven-day week. A year is dictated by the time it takes for the earth to orbit the sun, a day is dictated by the rotation of the earth. A month is more or less related to the lunar cycle (about twenty-seven and a quarter days) although by that reckoning there should really be thirteen months in a year.

Well, seven days is (not exactly, but as close as you can get with full days) the time between two subsequent different lunar phases: From new moon to half moon (waxing) to full moon to half moon (waning) and back to new moon is always about seven days each. It hasn’t been conclusively proven that this is the backgound for the seven-day week, but it is a common supposition.

I think it’s more internal trade that leads to some sort of 7-ish day long week. People who make a living in trade or the trades cannot just work every day without exception without going nuts and plus, need days to buy and sell things themselves. So a commonly agreed on day to do so seems natural.

(Farmers, of course, have times of the year when they need to work every day, all day, and times when they can’t work productively 5-6 days a week, so their schedule is more variable.)