This is a dialectual locational name derived from the hamlet of Knapton and now part of the Parish of Acomb near York, or from a similar village of Knapton in Norfolk. The name is Olde English pre 9th century and means 'The Farm (ton) on the Hill Top', from Knop or Knob - a round proturberance. This type of locational name was given either to the Lord of the Manor as in this case, the 'Lord' also being female which was not uncommon, or to a former inhabitant who moved to another area, as in Thomas Cnapeton, 1273, Suffolk. These movements were also a familiar source of mis-spelling. The first recorded spelling of the family name is shown to be that of Estrilda de Knapeton which was dated 1272, The Hundred Rolls of Norfolk during the reign of King Edward I, The Hammer of the Scots, 1272 - 1307 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.