In 1229 July 29, Mauritio de Gaunt (Maurice de Gaunt; Gant; Ghent; Maurice Paynel) was granted, by Henry III, (In year 13 of his reign) a Royal Pardon licence to crenellate Beverestan (Beverstone)

"Pro Mauritio de Gaunt de castro suo de Beverestan.- Rex omnibus ad quoa presentes litere pervenerint, salutem. Sciatis quod concessimus pro nobis et heredibus nostris dilecto et fideli nostro Mauritio de Gaunt et heredibus suis, quod castrum suum quod firmari fecit apud manerium suum Beverestan stet et remaneat inperpetuum ibidem prout nunc firmatum est. In cujus etc. fieri fecimus. Teste rege, apud Sanctum Neotum"

Granted at St. Neots, by King.

King writes "This is plainly an ex post facto licence, for a pre-existing castle."

Original source is

• Calendar of Patent Rolls (1225-32) p260

(In fact, the original source given is usually a transcription/translation of what are precious medieval documents not readily availably. It should be noted that these transcription/translations often date to the nineteenth or early twentieth centuries and that unwitting bias of transcribers may affect the translation. Care should also be taken to avoid giving modern meaning to the medieval use of certain stock words and terms.)

Significant later source are;

• Coulson, C., 1994, 'Freedom to Crenellate by Licence - An Historiographical Revision' Nottingham Medieval Studies Vol38 p92n17
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p186n4

Gant , Maurice de (c.1185–1230)

Gant [Ghent], Maurice de [Maurice fitz Robert, Maurice Paynel] (c.1185–1230), magnate, was heir to two major estates: the barony of Beverstone in Gloucestershire inherited from his father, Robert fitz Robert (d. 1194), a younger son of Robert fitz Harding, lord of Berkeley; and the barony of Hooton Pagnell in Yorkshire, which came to Maurice from his mother, Avice, daughter of Alice Paynel and Robert de Gant. Together these brought Maurice land in half a dozen counties, focused upon the honours and castles of Beverstone in Gloucestershire and Leeds in Yorkshire. (Vincent)
Maurice had lost some lands (but not Beverstone) after his revolt in 1215 and was involved in litigation to regain these after his pardon in 1217. He served Henry III as a soldier and had some royal appointments, such as justice on eyre, but does not appear to have had a particular royal association. Before Gant sailed for Brittany in 1230 he had surrendered his rights in Beverstone to the king. Was this licence fundamentally about royal recognition of those rights.

Biographical source include;

• Nicholas Vincent, ‘Gant , Maurice de (c.1185–1230)’, Oxford Dictionary of National Biography, Oxford University Press, 2004 [http://www.oxforddnb.com/view/article/10460, accessed 16 March 2008]
  

More details about licences to crenellate can be found here.

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