In 1311 May 28, Nicholaus de Sancto Mauro (Nicholas Seymour) was granted, by Edward II, (In year 4 of his reign) a Royal licence to crenellate Eton Meysi (Castle Eaton)

"Licence to Nicholas de Sancto Mauro to crenellate his dwelling-house (mansum suum) of Eton Meysi, co. Wilts."

Granted at Berwick-on-Tweed, by privy seal.

Original source is

• Calendar of Patent Rolls (1307-13) p361

(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, 2006, Greater Medieval Houses Vol3 (Cambridge) p695
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p505n37
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p406

More details about licences to crenellate can be found here.

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