This is an original Lincolnshire locational name which is a combination of the elements 'Torp' a Norse-Viking word for a Farm or Hamlet, and 'Aes' the pre 7th Century English meaning East - 'The East Farm'. The village of (now) 'Aisthorpe' is first recorded in the Domesday Book of 1086 as Aestorp and Estorp, and in 1115 as Esttorp. The surname recordings commence later, however local dialectual pronunciation caused the letters 'O' and 'R' to be transposed on some 'Aisthorpe' 18th Century spellings as in Henry Aistrop who was a witness at St. Martins in the Field, on May 12th 1767. This particular Westminster Church being strangely associated with the recordings of the Aistrop name. The first recorded spelling of the family name is shown to be that of John de Esthop, which was dated 1275, The Pipe Rolls of County Suffolk, 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.