Book: Origin Of The Names Of The Days by Aengor
Digging into the history of the 7-day week is a very complicated matter. Authorities have very different opinions about the history of the week, and they frequently present their speculations as if they were indisputable facts. The only thing we seem to know for certain about the origin of the 7-day week is that we know nothing for certain.The common explanation is that the seven-day week was established as imperial calendar in the late Roman empire and furthered by the Christian church for historical reasons. The British Empire used the seven-day week and spread it worldwide. Today the seven-day week is enforced by global business and media schedules, especially television and banking.
The names of the days are in some cases derived from Teutonic deities or, such as in Romance languages, from Roman deities. The early Romans, around the first century, used Saturday as the first day of the week. As the worshipping of the Sun increased, the Sun's day (Sunday) advanced from position of the second day to the first day of the week (and saturday became the seventh day).
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