Counts of Clermont-Tonnerre

Clermont-Tonnerre is the name of a French noble family, members of which played some part in the history of France, especially in Dauphiné, from about 1100 to the French Revolution (1789–99).

Sibaud, lord of Clermont in Viennois, who first appears in 1080, was the founder of the family. His descendant, another Sibaud, commanded some troops which aided Pope Calixtus II in his struggle with the Antipope Gregory VIII. In return for this service, it is said that the pope allowed him to add certain emblems, two keys and a tiara to the arms of his family.

A direct descendant, Ainard (died 1349), called vicomte de Clermont, was granted the dignity of captain-general and first baron of Dauphiné by his suzerain Humbert, dauphin of Viennois, in 1340; and in 1547 Clermont was made a county for Antoine (died 1578), who was governor of Dauphiné and the French king's lieutenant in Savoy. In 1572, Antoine's son Henri was created a duke, but as this was only a brevet title it did not descend to his son. Henri was killed before La Rochelle in 1573. In 1596 Henri's son, Charles Henri, count of Clermont (died 1640), added Tonnerre to his heritage; but in 1648 this county was sold by his son and successor, François (died 1679).

A member of a younger branch of Charles Henri's descendants was Gaspard de Clermont-Tonnerre (1688–1781). This soldier served his country during a long period, fighting in Bohemia and Alsace, and then distinguishing himself greatly at the battles of Fontenoy and Lawfeldt. In 1775, he was created Duke of Clermont-Tonnerre, and made a peer of France. As the senior marshal (c. 1747) of France, he assisted as constable at the coronation of Louis XVI in 1774. His son and successor, Charles Henri Jules, governor of Dauphiné, was guillotined in July 1794, a fate which his grandson, Gaspard Charles, had suffered at Lyon in the previous year.

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