In 1329 Jan 25, Robertus de Arden [Ardern] was granted, by Edward III, (In year 3 of his reign) a Royal licence to crenellate Perthyng [Perchyng] (Perching Manor House)

"Licence for Robert de Ardern to creiiellate his dwelling houses (mansum suum) of Dratton, co- Oxford, and Perchyng, co. Sussex."

Granted at St. Albans, by privy seal.

licensed 1260, 1264, 1268, 1329. This licence issued together with one for Dratton Oxfordshire.

Original source is

• Calendar of Patent Rolls (1327-30) p357

(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) p439
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p479n54
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p409

More details about licences to crenellate can be found here.

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