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Emperor Constantine I officially designated the dies Solis Invicti as the empire
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March 7

Constantine Declares Sunday: Rome Rests on Christian Law

Emperor Constantine I officially designated the dies Solis Invicti as the empire's day of rest, embedding a pagan festival into Roman law. This decree established Sunday as the standard weekly holiday across the Christianized West, shaping the rhythm of work and worship for centuries to come.

March 7, 321

1705 years ago

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