This is a locational name which is of Olde English pre 8th century origin and translates as either 'one who lived on a hillside covered with thorn trees', or was a former inhabitant of one of the villages called Thornborough (Bucks) or Thornbrough (Northumberland or Yorkshire) or Thornbury (Yorkshire, Devon, Gloucester or Hereford). There are no less than ten modern spellings including: Thornbery, Thornber, Thornburrow, Thornburgh etc. and recordings include Robert de Toreneberg of Yorkshire in 1219, and Hugh de Thornburgh in 1327. The first recorded spelling of the family name is shown to be that of Marherus de Torneberga which was dated 1176 The Pipe Rolls of Berkshire during the reign of King Henry II The Deceiver of the Irish 1154-1189 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.