12 hour time is a *very* ancient system that traces back to the Mesopotamian empires.
They had a cultural fixation on the number 12, used a base-12 numerical system, and divided up most things into 12ths whenever possible – including day and night.
The 12 hours of day and 12 hours of night system spread throughout Europe and the Middle East and has defied multiple attempts to change it over the centuries.
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