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Pope Gregory XIII Promulgates the Gregorian Calendar

2/24/1582
Pope Gregory XIII, portrait by Lavinia Fontana, 16C.
Image Source: en.wikipedia.org
Pope Gregory XIII, portrait by Lavinia Fontana, 16th century.

On February 24, 1582 Pope Gregory XIII issued a papal bull, Inter gravissimas, the founding document of the Gregorian calendar. It was printed on March 1, 1562.

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Religious Texts / Religion