In 1374 May 5, Willielmus de Thorp (William Thorp) was granted, by Edward III, (In year 48 of his reign) a Royal licence to crenellate Makeseye (Maxey Castle)

"Licence for William de Thorp to crenellate his manor (manerium) of Makeseye, co. Northampton."

Granted at Westminster, by For 1 mark paid in the hanaper.

A mark (13s 4d) was paid for the licence.

Original source is

• Calendar of Patent Rolls (1370-74) p434

(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 p321n16
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p417

More details about licences to crenellate can be found here.

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