Pope Gregory XIII
pope of the Catholic Church from 1572 to 1585 (1502–1585)
Pope Gregory XIII (Latin: Gregorius XIII, Italian: Gregorio XIII, born Ugo Boncompagni; 7 January 1502 – 10 April 1585) 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.
Early biography
Youth
Ugo Boncompagni was born the son of Cristoforo Boncompagni (10 July 1470 – 1546) and Angela Marescalchi, and paternal grandson of Giacomo Boncompagni and Camilla Piattesi, in Bologna, where he studied law and graduated in 1530. He later taught jurisprudence for some years, and his students included notable figures such as Cardinals Alexander Farnese, Reginald Pole and Charles Borromeo. He had an illegitimate son after an affair with Maddalena Fulchini, Giacomo Boncompagni, but before he took holy orders, making him the last Pope to have left issue.
Career before papacy
At the age of 36, he was summoned to Rome by Pope Paul III (1534–1549), under whom he held successive appointments as first judge of the capital, abbreviator, and vice-chancellor of the Campagna e Marittima.
Pope Paul IV (1555–1559) attached him as datarius to the suite of Cardinal Carlo Carafa. Pope Pius IV (1559–1565) made him Cardinal-Priest of San Sisto Vecchio and sent him to the Council of Trent.
In the year 1552, Ugo Boncompagni confirmed the paternity of his son Giacomo (or Jacopo). As stated in the online Archivio Digitale Boncompagni Ludovisi: "One of the most valuable items to emerge from the new archival finds from the Villa Aurora is an autograph declaration in Latin and Italian dated 22 December 1552 by Ugo Boncompagni (1502–1585, from 1572 Pope Gregory XIII).
The public source identifies “Pope Gregory XIII” as pope of the Catholic Church from 1572 to 1585 (1502–1585). This brief keeps that definition visible, then builds a research path around Pope, Gregory and XIII.
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This entry incorporates text from “Pope Gregory XIII” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.