In 1340 Oct 2, Johannes de Ferrers (John Ferrers) was granted, by Edward III, (In year 14 of his reign) a Royal licence to crenellate Beer Ferres [Beer Fereres] (Bere Barton, Bere Ferrers)

"Licence for John de Fereres to crenellate his dwelling-place (mansum) of Beer Fereres, co. Devon."

Granted at Andover, 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 (1340-43) p51

(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
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p350, 413

More details about licences to crenellate can be found here.

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