As a follow question, did Ancient China, India, the Incas and Aztecs, etc. have have a notion of weeks? Most civilizations had a notion of months because of the lunar cycle. Also, which civilization invented the notion of week? Was it the Romans?
Henry Ford was one of the first to broadly institute a 5-day workweek to improve employee output and morale. At the time, there were 6 day weeks and unlimited hours, but Ford proved that you could do as much in 5 days with less over-worked employees.
Later, FDR signed the Fair Labor Standards Actfederally limitng hte work week to forty hours and 8 hours per day. in the US.
As many nations modernized after WWII, fair workplace standards were taking shape all over the world. The European Social Charter brought the working week to countries in Western Europe and helped bring working conditions to the modern standard.
Finally, efforts in UN Members and other nations mandated current standards of living and workplace treaties. That pretty much unified everyone into the modern standard of workweeks and hours.
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