The pope who deleted ten days from the calendar

In 1582 Pope Gregory XIII reformed the calendar to correct the drift the old Julian system had let build up in the seasons. Under the new Gregorian calendar, Thursday 4 October 1582 was followed directly by Friday 15 October 1582 — so ten dates, the 5th through the 14th, simply never existed. That calendar is the civil standard used worldwide today.

One of many fact-checked wonders across eight traditions at The Spring of Wisdom.