"Grant, at the instance of Queen Eleanor, to William le Moyne that he may close and strengthen his house at Ogre, Co. Dorset, with a good dyke and stone wall, but without making crenellations."
Granted at Cambridge,
Specifically not a licence to crenellate but important as a example of licence to fortify with this rare exemption.
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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