This ancient English surname is claimed by the academics to be a short form or nickname of the female name Gillian, introduced by the Normans after 1066. However all the early recordings such the reverse, that it is male, and if so it is a derivation from the Olde English 'Gylle', which originally described one who lived in a valley. The medieval period from approximately the year 1200 to the year 1450 was the one in which almost all surnames were created. It has been said that by the latter date everybody had one, whilst in the century after Domesday Book (1086) only a few, perhaps 5% of the population had such names. This does not mean that those people who had them in 1450 have always kept them, or even those that did kept the same spelling, because in over nine out of ten names, this was not the case. In this case our short form is recorded as Jill, Gill, Gelle, Gell and Jell, being at various times both a surname and a personal name. The first known recording is as a personal name Gelle Bakur being recorded in Wakefield, Yorkshire, in 1275, the form of the name suggesting that the holder was male! A similar recording is that of Gelle Winter in the 1279 Hundred Rolls of Cambridge, which again suggests a possible male name. The early surname recordings include John Gelle of York in 1301 Subsidy Rolls, and Thomas Gele, also of York in 1379, but this time in the infamous Poll Tax rolls of the city. The first recorded spelling of the family name is shown to be that of John Jelle, which was dated 1296, the Subsidy Rolls of the county of Sussex, during the reign of King Edward 1st, 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.