In 1305 April 5, Robertus de Reynes (Robert Reymes) was granted, by Edward I, (In year 33 of his reign) a Royal licence to crenellate Shortflat (Shortflatt Tower)

"Licence for Robert de Reymes to creiiellate his dwelling places (mansum suum) of Shortflat and Eydon, co. Northumberland."

Granted at Westminster, by privy seal.

Same licence as Aydon Castle

Original source is

• Calendar of Patent Rolls (1301-7) p328

(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) p159
  Bates, C.J., 1891, Border Holds of Northumberland (London and Newcastle: Andrew Reid) p8
  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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