"Notification by Henry I to all his lieges of Kent: That he confirms to the church of Canterbury and to Abp. William, and all his successors, the custody and constabulary of Rochester Castle for ever, and this by the counsel of his barons; and that they may make a fort (municionem) ot tower as they please.
Witnesses: Roger Bp. of Salisbury; G[eoffrey] the Chancellor; William de Tancarville; Geoffrey fitz Payn."
Granted at Winchester,
Although this document has been considered by some as a licence to crenellate the current opinion rejects this as a licence to crenellate.
Date from John of Worcester who puts it in the year beginning Christmas 1126. Henry was at Winchester in January (A.S.C.). The Lambeth MS. (in margin) gives 1125. The entry is written in on p. 18 of the Lambeth MS. and p. 23 is an inserted schedule. P. 18 notes 'Hujus tantum habetur pars cum sigillo' and p. 188 'Hec invenitur'.
A licence to extend an existing castle rather than to build anew but has been considered a licence to crenellate. One of the earliest documented examples of royal permission to build a fortification, although Coulson calls this essentially a custody agreement. The existing great tower resulted.
Original source is
(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;
More details about licences to crenellate can be found here.
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