"Conceda etiam eidam Gaufredo quod novum castellum quod firmavit super Lviam stet et remaneat ad efforciandum ad voluntatem suam. Concedo etiam ei quod firmet unum castellum ubicunque voluerit in terra sua, sicut et per aliam cartam meam concessi, et quod stet et remaneat."
Granted at Oxford,
Although this document has been considered by some as a licence to crenellate the current opinion rejects this as a licence to crenellate.
A charter between Empress Matilda and Geoffrey de Mandeville, part of his 'king making' activities during the Anarchy, an similar grant (Round, p142) by King Stephen may predate Matilda's. The identification with South Mymms castles has been made but is not certain, an alternative might be the site of a possible motte at Bow, Middlesex. Not, in a meaningful sense, a licence to crenellate although has been called this by some.
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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