In 1337 Aug 2, Matilda quae fuit uxor Willielmi de Ferrers [Feriers], chivaler (Mathilda, widow of William Ferrars) was granted, by Edward III, (In year 11 of his reign) a Royal licence to crenellate Byr (Bere Barton, Bere Ferrers)

"Licence for Matilda late the wife of William de Feriers, knight, to crenellate her dwelling-place (mansum) of Byr, co. Devon."

Granted at Westminster, by privy seal.

Fortified Manor House with a licence to crenellate granted to Mathilda, widow of William Ferrars in 1337 and to John Ferrers in 1340.

Original source is

• Calendar of Patent Rolls (1334-38) p558

(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;

• Emery, Anthony, 2006, Greater Medieval Houses Vol3 (Cambridge) p695
  Higham, R. A., 1988, 'Devon Castles: an annotated list' Proceedings of the Devon Archaeological Society Vol46 p146
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p124n40
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p412

More details about licences to crenellate can be found here.

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