jurist who, as chancellor of France during most of the period from 1717 to 1750, made important reforms in his country's legal system.

The son of Henri d'Aguesseau, intendant (royal agent) of Languedoc, he was advocate general to the Parlement (high court of justice) of Paris from 1690 until 1700. As attorney general in that Parlement from 1700 to 1717, he opposed papal intervention in the affairs of the French Roman Catholic Church and resisted (though unsuccessfully) the promulgation in France of the bull Unigenitus (1713), which condemned the Jansenist faction in the church.

Philippe II, duc d'Orléans, regent for young King Louis XV (ruled 1715–74), made him chancellor and keeper of the seals in 1717, but Aguesseau's opposition to the government's financial policies caused the Duc to exile him to Fresnes in the following year. Recalled in 1720, Aguesseau reversed himself and helped promote acceptance of Unigenitus. Nevertheless, he again forfeited the chancellorship when Cardinal Guillaume Dubois became chief minister in 1722. In 1727 Aguesseau was reinstated as chancellor by the new chief minister, Cardinal André-Hercule de Fleury, who instructed him to continue the codification of French law begun under King Louis XIV (ruled 1643–1715).

Hence between 1731 and 1747 he obtained from Louis XV three important ordinances on donations, testaments, and successions. The Parlements prevented Aguesseau from extending the scope of his work, but he did improve court procedures and achieve greater uniformity in the execution of the laws.