Origins of du Plessis and du Plessis de Richelieu The later “du Plessis” family may have lived in Pontus under King Mithdrates and after he was defeated by the Roman general in 66 BC, they Pompey accompanied Prince Sigge from Asia Minor via the present Russia to Norway and later went to France with the Viking leader Rollo and served him as one of his subordinate nobles. The first recorded member of the family is Osulf son of Frame, born about 961 Died about 1030. His son, Grimoult du Plessis, born about 1000 and died about 1047 who took part on a revolt against William I, Duke of Normandy (Later known as William the Conqueror) with some of William’s other noble vassals. The rebels lost a battle against William I, Duke of Normandy aided by Henry I, King of France, after which Grimoult was imprisoned in a dungeon at Rouen, where he soon died and was buried in his fetters. This was why he was considered a traitor of Valognes et de Val-és-Dunes. The surname "du Plessis" comes from the fortified site of Plessis-Grimoult, (The bailey castle of Plessis-Grimoult, called Calvados is presented in the form of an oval curtain wall 50 to 60 meters in diameter, made of earth ramparts at the top of which stand the remains of a fortified gate and a small masonry tower.) it was built by Grimoult du Plessis. Geoffroy du Plessis added "de Richelieu" to the surname after 1488, when his wife's brother Louis de Clérembault, Lord of Richelieu, knowing that his death was imminent and having no heir, made his nephew Geoffroy du Plessis, “his main and executory heir, only and for all”. The du Plessis family became the Lords of the Manor of Richelieu, and took the name of du Plessis de Richelieu.
More: n 1688 Jean Prieur du Plessis settled in Cape Town, South Africa due to religious reasons.His father was Charl du Plessis, who was a surgeon in Poitiers. Charl was born about 1590 and his wife’s name is unknown. Charl’s Father was Jean du Plessis born about 1548 and married to Judith Anne du Plessis de Mornay She was born in Buhy, Vexin, France in 1555. Jean’s father was Francois II du Plessis, born about 1510 and died 1560 (Great grandfather of the Duke of Richelieu) His children were: CHARL PRIEUR DU PLESSIS. Gender: Male. Born on 18 April 1688 on board the ship “Oosterlandt”, and was baptised on 29 April 1668 on board the ship, anchored in Table Bay, Cape Town. Death: 18 September 1737 at Swartland or Stellenbosch, the Cape. JEAN-LOUIS DU PLESSIS. Gender: Male. Baptised: Baptized 13 February 1691. Death: Date: 14 March 1768. Details Tulbagh (Land van Waveren) JUDITH DU PLESSIS. Gender: Female. Baptised: Ireland, 1694 during the parents return to South Africa. MARIA DU PLESSIS. Gender: Female. Born in the Netherlands. Baptised 1702. ANNE DU PLESSIS. Gender Female, Baptised 1704. PIETER DU PLESSIS. Baptized Jun 1708. Gender: MaleDeath: Date: Died 31 Jan 1717 ELIZABETH DU PLESSIS. Gender: Female. Death: Date: 31 Jan 1717. From these many descendent's have spread, who had a great influence in South Africa. At about the same time one of the du Plessis de Richelieu family went to Denmark. The origional peson's name is not known yet. The earliest name known is: Johan Daniel du Plessis de RICHELIEU Born ca 1640 at Constance, Tyskland. Emigrated from Germany to Denmark/Norway about 1676. Died on 16th March 1695 at Eker, Denmark. This family is acknowledged as members of the Danish nobility and have delivered some persons of great influence, of whom a prominent member was Andreas du Plessis de RICHELIEU. Born 24 Ferbruary 1852 at Lojt, Abenaa. Denmark. He became the Commander-in-chief of the Royal Thai Navy, from January 16, 1900 to January 29, 1901 and a prominent business man in Denmark on his return, chairing 3 of the 4 largest companies in the country. There are indications that some members of this family settled in Canada, but I have no specific knowledge of these.