Pope Pius IV
pope of the Catholic Church from 1559 to 1565
Pope Pius IV (Italian: Pio IV; 31 March 1499 – 9 December 1565), born Giovanni Angelo Medici, was head of the Catholic Church and ruler of the Papal States from 25 December 1559 to his death, in December 1565.
Born in Milan, his family considered itself a branch of the House of Medici and used the same coat of arms. Although modern historians have found no proof of this connection, the Medici of Florence recognised the claims of the Medici of Milan in the early 16th century.
Pope Paul III appointed Medici Archbishop of Ragusa, and sent him on diplomatic missions to the Holy Roman Empire and Hungary. He presided over the final session of the Council of Trent. His nephew, Cardinal Charles Borromeo, was a close adviser. As pope, Pius IV initiated a number of building projects in Rome, including one to improve the water supply.
Life
Early life
Giovanni Angelo Medici was born in Milan on 31 March 1499 as the second of eleven children to Bernardino Medici and Clelia Serbelloni.
Giovanni Medici was the younger brother of condottiero Gian Giacomo Medici, and the maternal uncle of Charles Borromeo. Medici studied philosophy and medicine in Pavia.
“Pope Pius IV” enters the record as pope of the Catholic Church from 1559 to 1565. Crown Archives preserves that source wording while asking what Pope, Pius and pope can confirm, complicate or overturn.
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Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Jul 3, 2026. The linked authority identifier is Q161983. VIAF identifies the subject as 76309925. The Library of Congress control number is n84133262. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1499, 1565 and 1559.
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This entry incorporates text from “Pope Pius IV” 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.