Pope Gregory XIII Statue by Pietro Paolo Olivieri - Catholic Stock Photo

Pope Gregory XIII, born Ugo Boncompagni, was head of the Catholic Church and ruler of the Papal States from 13 May 1572 to his death in 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. Source

Pietro Paolo Olivieri (1551–1599 ) was a sculptor and Italian architect. Olivieri was the typical exponent of late- sixteenth-century mannerism. Source