The Gatehouse website record of a licence to crenellate for Bridgewater Castle granted on 1200 June 6

Original source is;

Hardy, T.D. (ed.), 1837, Rotuli Chartarum in Turri Londinensi asservati 1199-1216 (Record Commission) p. 70

(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. Licentia is best translated as 'freedom to' not 'permission'.)

Significant later sources are;

King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol. 2 p. 447n1 (somewhat confused)

Brewer , William (d. 1226)

Brewer , William (d. 1226), Sheriff of numerous counties, Baron of Bampton, Warden of the cornish tin mines, justice etc. 'was one of the half dozen or so men closest to the centre of power in England' (Turner p. 71)

Anyone looking for an instance of the exemplary royal servant of the middle ages could hardly do better than to examine the life of William Brewer. Aptly described by one modern writer as a ‘die-hard Angevin’, his career, spanning fifty years, was a model of loyalty and usefulness. He served four Angevin kings, among them King John, who is reported to have attributed to Brewer the ability to know his master's mind; it was John, above all, who made Brewer extraordinarily wealthy, and by the time of his death he was the master of some sixty knights' fees focused in the south-west, with a newly created caput at Bridgwater, Somerset. (Church)

Biographical source include;

S. D. Church, 2004, ‘Brewer , William (d. 1226)’ Oxford Dictionary of National Biography (Oxford University Press) online copy (subscription may be needed)
Turner, R.V., 1988, ‘William Briwerre’, in R. V. Turner, Men raised from the dust: administrative service and upward mobility in Angevin England p. 71–90

More information about licences to crenellate can be found here.

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