Louis Costaz
French mathematician (1767–1842)
Louis, baron Costaz (17 March 1767, in Champagne-en-Valromey (Bugey – 15 February 1842, in Paris) was a French scientist and administrator.
His brother Benoît Costaz (1761–1842) was bishop of Nancy. After studying mathematics, he taught at the military school at Thiron until 1793, then at the École polytechnique. A member of the Commission des Sciences et des Arts, he participated in the French invasion of Egypt, becoming secretary to the Institut d'Égypte and a member of the Privy Council of Egypt, as well as accompanying Bonaparte to Suez.
On his return to France, he presided over the Tribunat (1801–1803) and was entrusted with organising a school of arts and crafts. Prefect of the Manche area (1804–1809) and a baron de l'Empire from 1809, he was intendant of crown buildings (1809–1813) before becoming director general of bridges and roads (1813–1814). Summoned to the Conseil d’État in 1813, he was made prefect of Nord (as extraordinary commissaire) during the Hundred Days and retired from public life shortly afterwards.
Begin with the source’s own compact description: “Louis Costaz” is french mathematician (1767–1842). The dossier treats that line as a proposition to test through Louis, Costaz and French, not as a finished interpretation.
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Biographical claims are most persuasive when dates, appointments and relationships can be traced to records created close to the events described. The source revision retrieved here is dated Jun 29, 2026. The linked authority identifier is Q3261598. VIAF identifies the subject as 14869656. The Library of Congress control number is n85312019. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1767, 1842, 1761 and 1793.
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This entry incorporates text from “Louis Costaz” 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.