In 1333 March 2, Prior et Conventus de Spaldyng [ad requistitionem delicti clerici nostri Henrici de Edenestowe] (Prior and Convent of Spalding Abbey) was granted, by Edward III, (In year 7 of his reign) a Royal licence to crenellate Spaldyng (Spalding Priory)

"Licence, at the request of Henry de Edenestowe, king's clerk, for the prior and convent of Spaldyng to crcnellate their priory (Prioratum suum de)."

Granted at Pontefract, by King.

licence obtained at a time when Edenstowe and the abbot of Croyland where in armed conflict with Thomas Wake, lord of Liddel.

Original source is

• Calendar of Patent Rolls (1330-34) p411

(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;

• Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p89, 94
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p410

More details about licences to crenellate can be found here.

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