GASTINEAU DUPLESSIS, JEAN-BAPTISTE, “voyageur-associate,” fur-trader, militia officer, merchant; b.1671 in the Trois-Rivières region, son of Nicolas Gastineau Duplessis and Marie Crevier; buried 9 Feb. 1750 at Trois-Rivières.

Between 1694 and 1702 Jean-Baptiste Gastineau Duplessis went on several trading expeditions to the west as a “voyageur-associate.” On 9 June 1694 Daniel Greysolon* Dulhut hired him and some other men to go on a trading expedition to Michilimackinac. In 1701 he went to Detroit with his younger brother Louis and some 40 men, all of whom had been hired in the king’s name by Intendant Jean Bochart * de Champigny. The following year Gastineau Duplessis and his brother were employed by the Compagnie de la Colonie to go to Detroit with an expedition that was fully as large as the preceding one.

After these voyages Jean-Baptiste Gastineau Duplessis settled at Trois-Rivières where, it seems, he became lieutenant of the militia. We do not know at what moment he went into business, but around 1730 he entered into partnership with François-Étienne Cugnet to try to introduce buffalo into Canada; this enterprise was not, however, successful. Some years later Gastineau Duplessis had new business dealings with Cugnet, who in 1736 had become the chief shareholder in the Saint-Maurice ironworks company. Gastineau Duplessis furnished the ironworks with supplies valued at 7,071 livres 2 sols 6 deniers. He had trouble, however, in obtaining payment and, when Cugnet’s business began to fail, had to present a petition to Intendant Hocquart* in June 1741. In 1750, shortly after Gastineau Duplessis’s death, his wife encountered the same difficulties: this time Cugnet was sentenced in an ordinance from Intendant Bigot* dated 1 April to pay 2,722 livres 3 sols to Mme Gastineau Duplessis for the goods she had sold to the employees of the ironworks.

On 19 Nov. 1711 Jean-Baptiste Gastineau Duplessis had married Charlotte Le Boulanger at Cap-de-la-Madeleine. Three children were born of this marriage, including a daughter, Marie-Joseph, who in 1749 married Pierre-François Olivier* de Vézin.

Roland-J. Auger

AN, Col., C^11A, 53, ff.228–30. ANQ, NF, Ord. int., 1^er, avril 1750. ANQ-M, Greffe d’Antoine Adhémar, 9 juin 1694. PAC Report, 1904, app.K. Bonnault, “Le Canada militaire,” APQ Rapport, 1949–51, 522. Massicotte, “Répertoire des engagements pour l’Ouest, APQ Rapport, 1929–30, 202, 206–7. P.-G. Roy, Inv. ord. int., III, 164. Tanguay, Dictionnaire. Albert Tessier, Les forges Saint-Maurice, 1729–1883 (Trois-Rivières, Qué., 1952). Edgar Le Noblet Du Plessis, “Nicolas Gatineau, sieur du Plessis,” SGCF Mémoires, IV (1950–51), 23–39 P.-G. Roy, “Les bœufs illinois,” BRH, XXIII (1917), 275–84.