In 1321 March 12, Henricus de Bello Monte, Consanguineus Regis was granted, by Edward II, (In year 14 of his reign) a Royal licence to crenellate Whitewyk (Whitwick Castle)

"Licence for Henry de Bello Monte to crenellate his dwelling-place (mansum) of Whitewyk, co. Leicester."

Granted at Henley, by privy seal.

The building resulting from this licence may have provoked the attack by Sir John Talbot. Beaumont claim to the land was from wife's inheritance and, it seems, Talbot felt he had a claim to Whitwick.

Original source is

• Calendar of Patent Rolls (1317-21) p571

(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 p120-1
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p258n23
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p408

More details about licences to crenellate can be found here.

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