Recorded in many spellings including Aceter, Awcester, Assatur, Assiter, and others, this is an English surname. It is either a transposed and dialectal spelling of the city of Exeter in Devon, or is perhaps from some now 'lost' pre-medieval and Roman site, of which the only public reminder in the 20th century would seem to be the surname in its varied forms. It is known that over three thousand surnames of the British Isles do originate from now 'lost' villages and even towns, so whilst it still remains unusual, it is not by any means a unique situation. The name is clearly from the Roman word 'castra' meaning a camp or fortress, with Exeter itself over the past two thousand years being recorded as Iska, Escancastre, and Execestra. Locational surnames were also 'from' names. That is to say names given to people after they left their home village to move somewhere else. The easiest way to identify such strangers was to call them by the name of the place from whence they came. Spelling over the centuries being at best indifferent, and local dialects very thick, often lead to the creation of 'sounds like' spellings. Examples of the recordings include Mathias Assatur christened at Harrow on the Hill, Middlesex, on February 28th 1574, and Margaret Assiter who was christened at the same church, but on January 13th 1635.