Where in history is the starting point of modern week day count?

https://lemmy.world/post/2340523

Where in history is the starting point of modern week day count? - Lemmy.world

I mean, if today i.e. is Sunday then someone long time ago should have said “Today will be Sunday” for the first time in a period from today that is multiple of seven. I was assuming that it was Pope Gregory XIII in October 1582, but looks like he is not. I failed in googling and duckduckgoing out the answer, so I ask for Lemmy’s collective wisdom!

From weeks in general: en.wikipedia.org/wiki/Week

The modern seven-day week can be traced back to the Babylonians, who used it within their calendar. Other ancient cultures had different week lengths, including ten in Egypt and an eight-day week for Etruscans.

There’s probably a rabbit hole to go down to get into the mindset of who decided that a seven day week was a better system then what the neighbors are using. Babylonian astronomy and mathematics at the time likely played a role.

en.wikipedia.org/wiki/Babylonia

And overall there’s a rich history to how we divide up the years in calendar reform.

en.wikipedia.org/wiki/Calendar_reform

Personally, I’ve fallen in love with the international fixed calendar. It proposes getting rid of the 30 days hath November nonsense and making all months 28 days. Take all the month-ends and combine them into a new month Sol, and since 28 × 13 is 364, create a new holiday called world day that is part of no week, no month, just doin’ it’s own thing. Add on a monthless leap day when needed and like magic, months are now a functional unit of measurement. 1 month = 28 days.

en.wikipedia.org/…/International_Fixed_Calendar

Week - Wikipedia

As a programmer that whole month less day thing sounds like a total nightmare.