In 1306 Sept 16, Walterus de Langton, Coventr. et Lych., Episcopus (Bishop Walter de Langton) was granted, by Edward I, (In year 34 of his reign) a Royal licence to crenellate alibi per omnia loca quae idem episcopus habet in Anglia (or elsewhere in England, wherever he pleases)

"domos quas fieri fecit apud Beudesert et Asheby David et alibi per omnia loca quae idem episcopus habet in Anglia"

Granted at Blenkinsop, by privy seal.

Thompson writes "Bishop Langton received, in 1306, a licence to crenellate Beaudesert, Staffs and Ashby, Northants and all episocopal palaces in England." The PRO transcribe this as "or elsewhere in England, wherever he pleases" Lichfield had been licenced in 1299, the bishop had several other houses in the see, particularly at Coventry, and his London Inn but here is no evidence of particular work resulting from this licence elsewhere.

Original source is

• Calendar of Patent Rolls (1301-7) p462

(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;

• Roy Martin Haines, ‘Langton, Walter (d. 1321)’, Oxford Dictionary of National Biography, Oxford University Press, 2004 [http://www.oxforddnb.com/view/article/16046, accessed 19 Nov 2007]
  Thompson, M.W., 1998, Medieval bishops' houses in England and Wales (Aldershot: Ashgate Publishing) p167
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p405

Langton, Walter (d. 1321)’

Langton, Walter (d. 1321), administrator and bishop of Coventry and Lichfield... Guisborough describes Langton as a poor clerk; elsewhere he is said to have been in Edward I's service from his youth. Appearing first as a wardrobe clerk in 1281–2... In 1305 he was a member of an embassy sent to Lyons to secure papal absolution from Edward's oath to maintain the charters, and attended Clement V's consecration on 14 November. On 2 July 1306, jointly with Archbishop William Greenfield of York (d. 1315), Langton was appointed keeper of the realm during Edward I's absence in Scotland. (Haines)

Biographical source include;

• Roy Martin Haines, ‘Langton, Walter (d. 1321)’, Oxford Dictionary of National Biography, Oxford University Press, 2004 [http://www.oxforddnb.com/view/article/16046, accessed 19 Nov 2007]
  

More details about licences to crenellate can be found here.

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