"Considering that the site of the manor of Thomas Fitz William, king's squire, at Malberthorpe, co. Lincoln, where the said Thomas dwells, is on the sea coast, the king, of special grace, has granted the said Thomas licence that he may put a ditch (fossare) to his manor and enclose the same with walls of 'breke,' stone and mortar (muris de breke lapides et c'clicinis) and crenellate and embattle it and make towers and fortresses there and so hold it to him and his heirs."
Granted at Coventry, by King and of the said date etc. {by authority of parliament}.
Presumably the risk from pirates or French raids was the reason that being by the sea was mentioned, although the Lincolnshire coast was not a prime target for either of these. Possibly the mention of the sea coast was useful in easing his neighbours concerns about his ambitions.
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;
Fitzwilliam, Sir Thomas (d. 1479), a Lincolnshire gentry family. His son, also Thomas, was to become Speaker of the House of Commons. King's Squire 1443-60; MP Lincs 1453-4. Lancastrian. In 1443 he was exempted from holding office against his will because the sea had taken his land at Mablethorpe. Some slight service on commissions and was a JP but no evidence of particular political ambition. It is difficult to see this licence as anything other than a reward for long, if unspectacular, service to the Crown by a man about to retire.
Biographical source include;
More details about licences to crenellate can be found here.
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