Died 1650, Paris, France | ||
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Claude de Mesmes, comte d'Avaux (1595–1650) was a 17th-century French diplomat and public administrator, one of France's leading diplomats in the first half of the century. He was Superintendent of Finances of France from 1649 to 1650.
His first major post was that of a French ambassador to the Republic of Venice (from 1627). Later, Count d'Avaux headed a diplomatic mission to Denmark and Sweden in 1634. In 1635, he contributed to the achievement of an armistice between Sweden and the Polish-Lithuanian Commonwealth in the Treaty of Sztumska Wieś, where he met many Polish magnates (like Rafał Leszczyński). Count d'Avaux concluded treaties between France and Sweden in 1638 and 1641, and during the years 1643–1648, he took part in the lengthy negotiations which led to the Peace of Westphalia, which ended the Thirty Years' War. However, d'Avaux was removed from the Congress of Westphalia in 1648, largely due to ideological differences and competition with the other French diplomats and with his superiors in France. Although this affair damaged his reputation, he ended his life serving the French government as a member of the high Council of the Realm.