In 1318 May 9, Henricus de Wylyngton was granted, by Edward II, (In year 11 of his reign) a Royal licence to crenellate Culverden [Culverton] (Willington Court)

"Licence for Henry de Wylyngton to crenellate his dwelling place (mansum) of Culverden, co. Gloucester."

Granted at Windsor, by King, on the information of Master Thomas dc Cherleton.

Original source is

• Calendar of Patent Rolls (1317-21) p141

(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) p211
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p407

Henry de Willington (b abt 1276- d. 1322)

Henry de Willington b abt 1276, of Shrivenham, Berkshire, England, d 1322, hanged after battle of Boroughbridge. He md Margaret de Freville abt 1295. She was b abt 1282. 3rd son of Sir Ralph de Willington of Willington Court & Umberleigh (Devon), Governor of Exeter Castle, Sheriff of Devon.
A supporter of Thomas, earl of Lancaster. He was executed in Bristol, slightly after the Earl's execution for treason in March 1321. His father and two elder brothers were both still alive in 1318 so quite why he is granted the licence for the family seat is unclear. He does seem to have been a noted soldier.

More details about licences to crenellate can be found here.

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