This very unusual and interesting name is of Olde Norse origin, being a topographical surname denoting residence on a piece of flat land. The derivation is from the Olde Norse word 'sletta', a level field, borrowed into Olde English as the dialectal 'sleet', meaning a flat meadow, or any level stretch of ground. The places in North Yorkshire called 'Sleightholme' and 'Sleights' derive from the same source. Topographically related surnames were among the earliest recorded, since natural and man-made features in the landscapes provided obvious identification of a person's residence. One Joane Sleet was married to John Cunisbie on the 10th May 1601 at St. Margaret's, Westminster, in London. The first recorded spelling of the family name is shown to be that of Ales Slet (christening), which was dated August 1540, Bletchingley, Surrey, during the reign of King Henry VIII, Bluff King Hal, 1509 - 1547. 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.