In 1259 Dec 20, Richard {de Clare} was granted, by Henry III, (In year 44 of his reign) a Royal licence to crenellate Tonebrugg (Tonbridge Town Defences)

"to close his town of Tonebrugg with a wall, and crenellate it, if he will."

Granted at Paris, by King present W. earl of Albemarle, J. Mansel, P. de Sabaudia and R. Walerand.

Clare, Richard de, sixth earl of Gloucester and fifth earl of Hertford (1222–1262), magnate. Richard was far too powerful a lord to insult by not giving a licence but this is far from his real military power base in south Wales.

Original source is

• Calendar of Patent Rolls (1258-66) p108

(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, Charles, 2007-8, 'On Crenellating, in Kent and Beyond - A Retrospection' The Castle Studies Group Journal Vol21 p189-201 esp p193-4

Clare, Richard de, sixth earl of Gloucester and fifth earl of Hertford (1222–1262)

Clare, Richard de, sixth earl of Gloucester and fifth earl of Hertford (1222–1262), magnate. Richard was far too powerful a lord to insult by not giving a licence but this is far from his real military power base in south Wales.

Biographical source include;

• Michael Altschul, ‘Clare, Richard de, sixth earl of Gloucester and fifth earl of Hertford (1222–1262)’, Oxford Dictionary of National Biography, Oxford University Press, 2004 [http://www.oxforddnb.com/view/article/5448, accessed 19 Nov 2007]
  

More details about licences to crenellate can be found here.

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