POITOU  , one of the old provinces of

France, which also formed one of the great military governments of the kingdom, was bounded on the N. by Brittany, Anjou and Touraine; on the S. by Angoumois and Aunis; on the E. by Touraine, Berri and Marche; and on the W. by the ocean . It was divided into Lower Poitou, which corresponded to the modern department of La Vendee, and Upper Poitou, now split into the departments of Deux-Sevres and Vienne . The principal towns in Upper Poitou were Poitiers the capital, Mirebeau, Chitellerault, Richelieu, Loudun, Thouars, Mauleon, Parthenay, Niort, &c.; and in Lower Poitou Fontenay-le-Comte, Maillezais, Lucon and Roche-sur-Yon . Ile d'Yeu or tle-Dieu and Noirmoutier belonged to the province . Ecclesiastically, Poitou was a diocese which was broken up in 1317 to form two new dioceses of Lugon and Maillezais; the seat of the latter was transferred in the 17th century to La Rochelle . For the administration of justice, Poitou was attached to the parlement of Paris . After 778 it formed part of the domain of the counts of Poitiers (q.v.) . Poitou (Poictou, Pictavia) takes its name from the Pictones or Pictavi, a Gallic nation mentioned by Caesar, Strabo and Ptolemy, and described by Strabo as separated from the Namnetes on the north by the Loire . It formed part of the territory known as Aquitaine (q.v.) . For the history see the Memoires of the Societe des Antiquaires de l'Ouest (1835 sqq.) and the documents published by the Archiveshistoriques du Poitou (1872 sqq.) ; also the Dictionnaire topographique de la Vienne, by L . Redet (1881) .