RATIA´TUM(πατίατον,), a town of the Pictones (Ptol. 2.7.6). Ptolemy mentions it before Limonum, and places it north of Limonum, and further west. Some editions of Ptolemy place Ratiatum in the territory of the Lemovices, but this is a mistake. In the records of a council held at Orléansin A.D. 511, the bishop of the Pictavi signs himself de civitate Ratiatica.The name was preserved in that of the Pagus Ratiatensis, from which comes the modern name of Pays de Retz. Gregory of Tours speaks of Ratiatum as infra terminum Pictavorum qui adjacet civitati Namneticae.The district of Retzwas taken from the diocese of Poitiersand attached to the diocese of Nantesin the time of Charles the Bald. Belley (Mém. de l'Acad. des Inscript. tom. 19. p. 729) fixes Ratiatum at the site of the two churches of St. Pierreand St. Opportune de Retz, which are near Machecouland on the Tenu, a small river in the department of La Vendée. The Tenuenters the sea near Bourgneuf, opposite to the Isle Noirmoutier(D'Anville, Notice, &c.Ukert, Gallien, p. 393).
[G.L]