Pope Gregory XIII (died 1585)

Pope Gregory XIII was head of the Catholic Church and ruler of the Papal States from 13 May 1572 to his death in April 1585. He is best known for commissioning and being the namesake for the Gregorian calendar, which remains the internationally accepted civil calendar to this day.

January 7 is the seventh day of the year in the Gregorian calendar; 358 days remain until the end of the year.