In 1315 March 12, Ranulpus de Albo Monasterio (made at the request of the venerable father W. bishop of Exeter) (Ranulf de Blanchminster) was granted, by Edward II, (In year 8 of his reign) a Royal licence to crenellate Inor [Ivor] (Ennor Castle)

"mansum suum de Ivor in...Insula de Sully, Cornub."

Granted at Westminster,

The earliest reference to Ennor Castle is in a deed of AD 1244 and by 1306 Ranulf de Blanchminster held the castle. A royal licence to crenellate the castle was granted to Ranulf in 1315 but in 1337, the castle along with the rest of Scilly was included in the lands of the newly created Duchy of Cornwall.

Original source is

• Calendar of Patent Rolls (1313-17) p262 [Transcribed as Inor]

(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 (New York) Vol2 p553n2
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p407 [Transcribed as Ivor]

More details about licences to crenellate can be found here.

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