In 1377 Dec 10, Willielmus, episcopus Cicestr (Bishop William Rede) was granted, by Richard II, (In year 1 of his reign) a Royal licence to crenellate Amberle (Amberley Castle)

"Licence for William, bishop of Chicester, to crenellate his manor (manerium) of Amberle."

Granted at Westminster, by privy seal.

Bishop William Rede gained a licence to crenellate in 1377, and built the present castle between 1377-1382. Re-licensed with other manors of the see of Chichester in 1447.

Original source is

• Calendar of Patent Rolls (1377-81) p76

(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) p439
  Thompson, M.W., 1998, Medieval bishops' houses in England and Wales (Aldershot: Ashgate Publishing) p168
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p476n2
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p418

More details about licences to crenellate can be found here.

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