This intriguing name is of early medieval Anglo-Norman French origin, and was introduced into England after the Norman Conquest of 1066. The surname derives from the habitual use of a nickname, as was frequently the case in the medieval period of surname creation; in this instance the nickname was one bestowed on an illegitimate child, and especially given to the illegitimate child of a priest. The name derives from the Anglo-Norman French "fitz, fiz", son, from the latin "filius", with "deu", God, from the Latin "deus". The nickname thus meant "child of God". The modern surname from this source can be found as Fido, Fidoe, Fydo(e) and Fiddy. One Edward Fido was christened on September 22nd 1629 at St. Mary at Hill, London, and the marriage of Thomas Fido and Lydia Lynk was recorded at St. James's, Duke's Place, London, on January 2nd 1688. The first recorded spelling of the family name is shown to be that of Walter Fideu, which was dated 1327, in the Pinchbeck Register of Suffolk, during the reign of King Edward 11, known as "Edward of Caernafon", 1307 - 1327. 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.