In 1352 Feb 11, Marmaducus le Conestable (Marmaduck, Constable of Holderness) was granted, by Edward III, (In year 26 of his reign) a Confirmation licence to crenellate Insulam de Flaynburgh (Beacon Farm, Flamborough)

"Licence for Marmaduke le Conestable to crenellate his dwelling place in (mansum suum infra) the isle of Flaynburgh, co. York."

Granted at Westminster, by p.s.

It is usually presumed this is either a copy or a repeat of the licence of the previous year although there was another possible fortified house in Flamborough at Beacon Farm. This licence is for his 'mansum' in Flamborough, the 1351 licence was for a 'chamber' within the manor of Flamborough. In this context 'chamber' probably refers to the tower house. I speculate that Marmaduck obtained a licence for his new tower on its near completion in 1351, then, having decided to continue to use the older manor at Beacon Farm, perhaps as subsidiary lodgings, decided to grandify this with some decorative crenellations and obtained a licence for this in 1352.

Original source is

• Calendar of Patent Rolls (1350-54) p225

(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;

• Emery, Anthony, 1996, Greater Medieval Houses Vol1 (Cambridge) p421
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p537n29
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p415

More details about licences to crenellate can be found here.

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