In ?1343, Thomas de Gournay (Thomas Gurney) was granted, by Edward III, (In year 17 of his reign) a Royal licence to crenellate Estharpetre (Richmont Castle, East Harptree)

"Thomas de Gournay or de Gurnay of Harptre.
Writ, 3 August, 17 Edward III
Somerset. Inq. taken at Somertone on Thursday before St. Lawrence, 17 Edward III.
He held nothing of the king in chief &c. but rendered 6s. 8d. yearly to the king for licence to crenellate (karnellandi) the castle of Estharptre."

This licence was revoked

Post mortum inquisition of Thomas de Gourney in 1343 records 'he held nothing of the King in chief, etc., but rendered 6s. 8d. yearly to the King for licence to crenellate (karnellandi) the castle of Estharpetre' Coulson writes "writ of Certiorari produced a new inquisition which omitted this detail [the yearly fee] (August 1347). There is no enrolment as calendared, so the licence was probably cancelled for non-payment. It was probably a Hanaper fee, due to be collected by the sheriff, wrongly entered as annual." I would add the speculation that perhaps the death of Thomas was the reason for the none payment and that 'yearly' is an error for 'to be paid this year'.

Original source is

• Calendar of Inquistions, Edward III Vol8 p287 No434

(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. Licentia is best translated as 'freedom to' not 'permission'.)

Significant later source are;

• Emery, Anthony, 2006, Greater Medieval Houses Vol3 (Cambridge) p695
  Coulson, C., 1994, 'Freedom to Crenellate by Licence - An Historiographical Revision' Nottingham Medieval Studies Vol38 p121
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p447n15a

Presumably Thomas Gurney, although some accounts have him alive in 1345, son of Thomas, traitor and supposed murderer of Edward II who died 1327. A remarkable act of forgiveness and reconciliation but fairly typical of Edward III. Gourney lands had been seized by the crown so part of this licence about re-establishing ownership as well as re-establishing relationships with the crown.

More details about licences to crenellate can be found here.

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