Recorded in several spelling forms including Trewhitt, Trewett, and Trewitt, this is an English surname but of pre 7th century Old Norse origins. It is locational, deriving from a place called "Trewhitt" in the parish of Rothbury, in the county of Northumberland, originally akingdom ruled by the Vikings. The placename is recorded as "Tirwit" in the early Yorkshire charters of the year 1150, and as Thyrewhyt in the same county in 1269. The name means "the dry wood clearing" derived from the Old Norse word "tri", meaning dry, resinous wood, with "thwaite", a clearing or meadow. This was a popular element in placenames in the north and north-western counties of England, where there was heavy Scandinavian settlement. Locational names were used especially by those former inhabitants of a place who moved to another area. Early examples of the surname recordings taken from authentic surviving church registers include: Anne Trewhitt, who married John Briggs at St. James's church, Dukes Place, London on the 25th November 1694. The first recorded spelling of the family name is shown to be that of John de Tyrwyt, which was dated 1256, in the rolls of the Assize Court of Northumberland, during the reign of King Henry III, 1216 - 1272. 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.