In 1378 May, John de Neville, knight, Lord of Raby (John, 3rd Baron Nevill) was granted, by Thomas Hatfield, Bishop of Durham, (In year 33 of his reign) a Durham licence to crenellate Raby (Raby Castle)

"Receives a licence to erect a castle on his manor of Raby"

Though couched in formal legal language, the document is singular in being written in French. It is a licence in the fullest terms to make a castle.

Original source is

• 1870, Report of the Deputy Keeper Public Records Vol32 p292

(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, 1996, Greater Medieval Houses Vol1 (Cambridge) p159
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p141n16
  Hodgson, J.F. 1880-9, Transactions of the Architectural and Archaeological Society of Durham and Northumberland Vol3 p123
  Grose, Francis, 1787, The Antiquities of England and Wales (London) Vol2 p107-8

More details about licences to crenellate can be found here.

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