In 1303 Jan 30, Ranulpus de Fryskeneye (Ralph Friskney) was granted, by Edward I, (In year 31 of his reign) a Royal licence to crenellate Friskeneye (Friskney Hall)

"Licence for Ranulph de Friskeneye to crevellate his dwelling-place (mansum suum) of Friskeneye, co. Lincoln."

Granted at Chertsey, by privy seal.

Original source is

• Calendar of Patent Rolls (1301-7) p103
  Calendar of Chancery Warrents (1244-1326) p169

(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;

• Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p404

More details about licences to crenellate can be found here.

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