In 1204 May 27, Thom de Burgo (Thomas de Burgh) was granted, by John, (In year 5 of his reign) a Royal licence to crenellate Leleshay (Lindsey; The Mounts)

"Rex tc. justic Sciatis qd dedim Thom de Burgo licenciam claudendi domum suam de Leleshay: et io vob mandam qd eu in no ipediatis.
T.G. fil peti ap Turri Lond"

Granted at Tower of London,

Original source is

• Rotuli de Liberateac de Misis et Praestitis Regnante Johanne (Hardy, T.D. ed., 1844, Record Commission) p104

(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 p462n14a

Thomas de Burgh (d. 1233)

Sir Thomas de Burgh, of Upper Arley, Staffordshire, and Cockfield, Suffolk, brother of Sir Hubert de Burgh (died 1243), Earl of Kent. Thomas de Burgh married Nesta de Cockfield, Sir Thomas de Burgh was a knight, and he died prior to 1233. (Douglas Richardson, Salt Lake City, Utah) castellan of Norwich (1215–16) (ODNB for Hubert de Burgh)

More details about licences to crenellate can be found here.

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