Established by Pope Gregory XIII on 23 January 1576, it was the first in East Asia in the modern era and played a key role in ...

Our modern calendar is the Gregorian calendar, named for Pope Gregory XIII, who reformed it in 1582 to correct some errors in ...

This week is significant, for religious reasons it has not always existed. It was in 1582, Pope Gregory XIII instituted a major reform of the calendar, which has since been almost universally adopted.