In 1342 Oct 6, William Lengleys, dilectus vallettus noster was granted, by Edward III, (In year 16 of his reign) a Royal licence to crenellate Heyheved (High Head Castle)

"Licence for the king's yeoman, William Lengleys, to crenellate his manor (manerium) of Heyheved."

Granted at Eastry, by privy seal.

A grant 2 days later reads "that whereas he holds the lawn of Ivetonfeld within the forest of lnglewode by demise of the keeper of the forest beyond Trent at a certain farm, he shall hold the same for life for the farm aforesaid. Licence also for him to assart 15 acres of land by the forest peroh within the lawn, and enclose the same with a little dyke and a low hedge, according to the assize of the forest, and hold the same for his life."

Original source is

• Calendar of Patent Rolls (1340-43) p536

(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) p263
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p100n86b
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p413

More details about licences to crenellate can be found here.

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