In 1394 Sept 1, Hugh Cheyne, chivaler was granted, by Richard II, (In year 18 of his reign) a Royal licence to crenellate Longefeld (Cheney Longville Castle)

"Licence for Hugh Cheyne, knight, to crenellate his manor (manerium) of Longefeld. "

Granted at Hereford, by privy seal.

Identified by Parker as Longfield, near Dartford, Kent.

Original source is

• Calendar of Patent Rolls (1392-96) p500

(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;

• King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p437n15
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p420

More details about licences to crenellate can be found here.

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