Parker footnotes "Probably Kingham, Chipping-Norton," Charles Coulson confirms this identification.

Although was to do considerable royal service this licence granted early in the career of a clearly ambitious man. The licence may represent a reward for military service in France and money from that service must have funded both building work and his subsequent career moves.

Gilbert de Chasteleyn first appears with Thomas Beauchamp in Calais in September 1346 where he is described as being from "kengham", possibly Kingham in Oxfordshire. Before that time he had acted in Warwickshire as a feoffee between John de Segrave and Sir Fulk de Birmingham. Immediately after serving with the earl he appears to have been a very prominent member of the west midlands' county community. He was an occasional charter witness for the earl; witnessing charters in Warwick as well as at the earl's manor of Sutton Coldfield. He was present in 1350 when one of the earl's retainers quitclaimed all the property he had acquired in Warwick in the service of the earl, showing an involvement in the earl's internal administration. However, he appears to have been of most use to the earl in local affairs and was appointed as under-sheriff of Warwickshire and Leicestershire in October 1351, holding the post until October 1354. Immediately prior to his appointment as sheriff, Chasteleyn appears to have attempted to build up a base for himself in the midlands; he acquired the Worcestershire manor of Frankley from John, son of John de Grafton in 1350, and in 1351 bought a messuage, two carucates of land, twelve acres of meadow and £8 rent from William Trussel in the Warwickshire manor of Loxley. He frequently served as justice of the peace with the earl, both in Warwickshire and Worcestershire throughout his time as sheriff, and was a commissioner into a break-in of the earl's parks of Elmley in 1349, and Sutton Coldfield in 1351. He appears to have used his experience in the administration of the earl of Warwick as a springboard for a career in the royal administration. Following his tenure as sheriff he sold the manor of Frankley in 1354, and thereafter appears to have travelled frequently in the service of the crown. In 1355, he was appointed by Edward to oversee the running of Titchfield Abbey in Hampshire, and in July of that year he was appointed steward of the household of the king's daughter Isabel. His last appointment appears to have been in 1358, when he was appointed as a commissioner in Northampton, whereafter he dramatically disappears from view. Chasteleyn's promotion into the royal household shows just how far an ambitious and talented household knight was able to progress at this time (Barfield)