In 1626 he married Marguerite Clerselier and had eight children. He was charged by Jules Mazarin and resided from 1646 to 1649 at the Swedish court and in Osnabrück, negotiating the Peace of Westfalia. He held a correspondence with Queen Christina of Sweden to whom he presented the French philosopher René Descartes. Descartes died of pneumonia (or was assassinated?) in his house at Mälaren, 300 meters from Tre Kronor (castle).
In 1651 Chanut departed to Lübeck to a Congress which had to mediate peace between Sweden and Poland. This failed, however, and in 1653 Chanut came back to Stockholm. He probably invited Pierre Bourdelot and Gabriel Naudé, but departed soon after the Netherlands, where he was ambassador till 1655. Back in Paris he became state counsellor. While Ludovico Santinelli was participant at the murder of Gian Rinaldo Monaldeschi at Fontainebleau. Christina promised Chanut Ludivico and his two helpers would have to leave her court. After his death his friend and brother-in-law Claude Clerselier, an editor, inherited all the manuscripts by Descartes and published them.
His Mémoires et Négociations (Memoirs and Negotiations) were published posthumously (1676).
- Journal du voyage de deux jeunes hollandais à Paris en 1656-1658 / publié par A.-P. Faugère, p. 65. 
- Pierre Chanut, ami de Descartes: un diplomate philosophe By Jean-François de Raymond 
- Gallica, Bibliothèque Numérique
- Bertrand Russell, A History of Western Philosophy p.537 (Folio Society, 2004, originally published in 1945).
- Descartes was 'poisoned by Catholic priest' - The Guardian, Feb 14 2010
- Quilliet, B. (1987) Christina van Zweden : een uitzonderlijke vorst, p. 258.