Trentemoult, Norkiouse and the island of “Madagascard”: when Rezé was an archipelago

North of Rezé, old maps show a small archipelago whose names changed over time: Trentemoult (or Trentemoux), Norkiouse, the Île des Chevaliers… Cut off from the mainland by the Seil, the islands were separated from one another by a watercourse. In 1285, Olive, widow of Mathieu de l'Île, handed lands to the Templars that took the name Île des Chevaliers, with Basse-Île downstream and Haute-Île upstream. A 1698 map calls it the “île de Madagascard”. As the Seil, cut off from the Sèvre as early as the sixth century, gradually dried up, Trentemoult, built on an island of rocky origin, was inhabited from Antiquity, geographer Loïc Ménanteau reminds readers in Rezé Mensuel.