This is a dialectal variant and localised form of the Cambridge village spelt as "Whittlesey". It is quite a normal practise in most countries to adopt slang forms of names, and particularly place names if they present some difficulty in pronunciation. Almost every area has an example, and in many cases the slang form has completely overtaken the original name. Of course it is always possible that in this case a place called "Whitsey" or a near equivalent may have existed, over five thousand village sites have disappeared since the 14th century, but if it did it would still have the same meaning as "Whittlesey". The origin is Olde English pre 10th century, and it very meaning points to the fen country of East Anglia. The derivation is from two elements "Witel" a recorded moneyer (Banker) and "ey" - an island, "Witel" being a person of considerable wealth in the year 973. It is not clear when the local surname form as Whitsey was adopted, but the village is recorded as "Witesie" in the 1086 Domesday Book. The surname forms are 18th century suggesting that in the late 17th century the original village was probably "cleared" to facilitate sheep farming, the inhabitants being forced to leave, and in doing so adopting as their surname, that of the former village. Examples of the name recordings include John Whitsey who married Sarah Bell at Stanwick, Cambridge on May 5th 1744, and Mary Whittlesea, who perhaps reverted to the village spelling, and who married William Smith at Peterborough on June 27th 1746. The first recorded spelling of the family name is shown to be that of Ann Whitsey, which was dated March 14th 1700, married George Knight at Higham Ferrers, Northants, during the reign of Queen Anne, the last Stuart monarch, 1702 - 1714. 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.