In 1200 April 10, Bishop Geoffrey Muschamp was granted, by John, (In year 1 of his reign) a Royal licence to crenellate Eccleshal (Eccleshall Castle)

Granted at Worcester,

A licence was granted by King John circa 1200 for the former moated site to become a castle.

Original source is

• Hardy, T.D. (ed.), 1837, Rotuli Chartarum in Turri Londinensi asservati 1199-1216 (Record Commission) p60b

(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 p106n55
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p454N14
  Thompson, M.W., 1998, Medieval bishops' houses in England and Wales (Aldershot: Ashgate Publishing) p165

Muschamp, Geoffrey de (d. 1208)

Muschamp, Geoffrey de (d. 1208), made bishop of Coventry in 1198 and was present at King John's coronation in 1199. Was an assiduous if not very note worthy bishop and does not seem to have held political office. He got the see through 'virtue of royal power' (Franklin) but the relationship with the king is obscure, although he was a protégé of Geoffrey, archbishop of York, the illegitimate son of Henry II.

Biographical source include;

• M. J. Franklin, ‘Muschamp, Geoffrey de (d. 1208)’, Oxford Dictionary of National Biography, Oxford University Press, 2004 [http://www.oxforddnb.com/view/article/10534, accessed 19 Nov 2007]
  

More details about licences to crenellate can be found here.

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