how and when did the whole world end up using a seven day week when there are multiple calendars? It’s not an obvious number…?


how and when did the whole world end up using a seven day week when there are multiple calendars? It’s not an obvious number…?

In: 7383

Not a great answer for you, but around the world, in all ancient cultures, it made sense to have a calendar as a celestial system, meaning it’s based on planets, stars, the sun and the seasons.

They all figured out that a “year” is a thing, that the seasons and weather repeats, that today of this year is going to be similar, weather wise, to today of next year. So they created the concept of a “year” based on getting the weather right in this sense, for example you should always plant your crops on a certain day every year, or harvest them, etc.

Our calendar gets it’s roots from a specific culture – the ancient Babylonians. While every culture around the world had a similar “year”, they all divided it up a bit differently, concepts of “months” “weeks” etc. varied from place to place.

The Babylonians loved the number 7, especially with mystical things. Why? Because of space. The Moon, Mars, Venus, Sun, Jupiter, Mercury, Saturn are all visible to the naked eye so it made sense in their minds to have 7 days named for each one. *Saturn*day, *Sun*day, *Moon*day, etc.

Now the Babylonian culture was thousands of years ago but this system passed around Europe and North Africa widely. In English our current “words” for the days derive from a mix of Latin and German roots but there are connections.

Jupiter (the planet) is tied to Jupiter (the God). Loosely, the Norse God “Thor” is culturally and thematically linked to Jupiter. *Jupiters*day became *Thors*day became Thursday.

Etc. etc.

Just case you are solely an English speaker, yes, these trends extend to the other Latin languages as well. In Spanish Luna means The Moon. So Moonday = Monday = Lunes.

it takes about 28 days for the moon to go from “full moon” to the next “full moon”.

this is something that people allover the world could easily observe (no light polution back then). now you can separate this “moon time” into four periods:

“kinda full” / “decreasing” / “kinda not there” / “increasing”.

each of those 4 phases is now 7 days.

What I want to know is why don’t we just have 13 months instead of 12, that way each month would be 28 days with only one outlier being 29. Enough of this sometimes 31 or sometimes 30 bullshit.

My reading on the subject is that a few cultures did weeks of different lengths but that a ton of cultures did 7 day weeks because there are 7 heavenly bodies that move in a pattern different from stars – the 5 visible planets plus moon and sun.

‘the world’ went to 7 day weeks due to western influence, but most were already doing that

The Hebrew and Muslim calendars both use a seven-day week because they’re related. The Roman calendar picked up a seven-day week after they converted to Christianity, because Christians go to church on the day after the Jewish Sabbath.

Our modern calendar is mostly Roman. Almost everyone uses this calendar now, or at least has to do business with people who use it. So now there’s a standard worldwide week.

It wasn’t always this way. The Chinese calendar, for example, sometimes used a seven day week, but mostly used shorter or longer weeks. Pagan Rome used an eight day week. The Maya calendar had no week.