In 1364 July 9, John de Delves was granted, by Prince Edward, The Black Prince, (In year 31 of his reign) a Chester licence to crenellate Dodynton (Doddington Tower)

"to fortify and kernellate his mansion at Dodynton with stone chalk and wood, and to hold the same so fortified, to himself and his heirs."

Granted at London, by letter of warrent out of Gascony.

King writes, citing page 522 that Ormerod gives no authority and "presumably a Chester licence.' Ormerod does give the Chester Recognizance Roll reference on page 519. The Black Prince was created earl of Chester in 1333.

Original source is

• 1875, Report of the Deputy Keeper Public Records Vol36 p143
  Chester Recognizance Roll, 38 & 39 Edw. III. m. 1d. (7), (8)
  Register of Edward the Black Prince Vol3 p469

(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., 1994, 'Freedom to Crenellate by Licence - An Historiographical Revision' Nottingham Medieval Studies Vol38 p122n109
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p70n7
  Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p95n2
  Ormerod, G., 1882 [2edn], History of the County Palatine and city of Chester (London) Vol3 p519

More details about licences to crenellate can be found here.

Please let me know if you see any errors, can add information or can otherwise help to improve this resource. Contact me