This interesting and most unusual name may derive from two possible origins. Firstly it may have been a nickname for a joyous, sprightly young lad, from the medieval English word "jolif", "joly", joyous, spirited, which occurs in a number of nicknames, plus the suffix cock, from the Old English pre seventh Century word "cocc", cock, applied to a lad who strutted about like a cock, hence "Jolif-cock", from which we get "Jellicoe". The name may also be a diminutive of "Julian", a Devon and Cornwall name, from a medieval personal name, from the Latin "Iuliqnus". The name first appears in records in the early 14th Century, (see below). John Jillicoe married Mary Brookes at St. Dunstan, Stepney London, on September 10th 1626, while at St. Andrews, Enfield in London, Addam, son of Jacob Jelico was christened in March 1646. Joseph son of Samuel and Martha Jellicoe was christened at St. Giles Cripplegate in 1691. The christening of one John, son of William Jellico took place at Maker in Cornwall on September 9th 1803. The first recorded spelling of the family name is shown to be that of William Gentilcorps, which was dated 1301, Writs of Parliament, during the reign of King Edward 1, known as "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.