This uncommon name is of Old French origin, and was introduced into Britain by the Normans after the Conquest of 1066. It is a locational surname, deriving from an Anglicized form of the placename Dumart-en-Ponthieu, in the Somme near Abbeville. Locational surnames throughout Europe were acquired by the lord of the manor, and local landowners, and especially by those former inhabitants of a place who had settled elsewhere, and were thereafter best identified with the name of their birthplace. At least three hundred modern English surnames have been traced back to French locational names introduced into England by followers of William the Conqueror; these people were mostly given extensive grants of land, and their name thus became localized. The modern surnames Dummet(t) and Dommet(t) are found mainly in Devonshire, where examples from Church Registers include the marriage of Jone Dummett and John Colliford in Uffculme, on May 11th 1579, and the marriage of John Dummett and Margerett Cannon at St. Martin's, Exeter, on February 6th 1618. The Coat of Arms most associated with the family depicts a gold saltire, wavy, between two gold fleurs-de-lis in pale and two gold mullets in fesse on a blue shield. The first recorded spelling of the family name is shown to be that of Aliz de Dummart, which was dated 1200 - 1201, in the "Pipe Rolls of Warwickshire", during the reign of King John, known as "Lackland", 1199 - 1216. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.