The Dragon and the Calendar - Pope Gregory XIII
February 9, 1581 Pope Gregory XIII, Creator of the Gregorian Calendar: A Signed Letter from 1581 – Papal Artifacts
April 10 - Pope Gregory XIII - Nobility and Analogous Traditional Elites
Pope Gregory XIII - Wikiwand
File:Coat of arms of Pope Gregory XIII Boncompagni.svg - Wikimedia Commons
Gregory XIII | Biography, Papacy, Gregorian Calendar, & Facts | Britannica
Pope Gregory XIII: Accomplishments & Legacy | Study.com
The Dragon and the Calendar - Pope Gregory XIII
The Dragon and the Calendar - Pope Gregory XIII
Pope Francis' Conn. appointment draws criticism
February 9, 1581 Pope Gregory XIII, Creator of the Gregorian Calendar: A Signed Letter from 1581 – Papal Artifacts
File:Gregory XIII - Ouroboros medal (1582).jpg - Wikimedia Commons
On this day in 1582: Pope Gregory XIII announces the new Gregorian calendar
April 10 - Pope Gregory XIII - Nobility and Analogous Traditional Elites
Pope Gregory XIII: Accomplishments & Legacy | Study.com
Rome for beginners and for the advanced, for the curious and the courageous.
Pope Gregory XIII,Ugo Boncompagni,Pope of the Catholic Church,1502-1585 | eBay
Pope Gregory XIII - Wikiwand
Pope Gregory XIII - PopeHistory.com
Pope Gregory XIII (1572-1585) of Gregorian Calendar fame b… | Flickr
The Dragon and the Calendar - Pope Gregory XIII
Pope Gregory XIII: Accomplishments & Legacy | Study.com
Pope Gregory XIII – Papal Artifacts
April 10 - Pope Gregory XIII - Nobility and Analogous Traditional Elites
Pope Gregory XIII | Italy On This Day
Pope Gregory the Great and St Matthias | Art for B Easter 7 – Hear what the Spirit is saying
