In 1261 Aug 14, Robert de Sancto Johanne (Robert de St John) was granted, by Henry III, (In year 45 of his reign) a Royal licence to crenellate Basing (Basing House)

"Grant to Robert de Sane to Johanne that he may fortify with a paling his house at Basing upon his dyke now thrown up (exstructa) there, and keep it so fortified at the king's will."

Granted at Windsor,

This was merely for an earthwork castle, a paling on the bank then thrown up. It is not clear whether it was recently thrown up.

Original source is

• Calendar of Patent Rolls (1258-66) p172

(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 p125n118
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol1 p197n2

More details about licences to crenellate can be found here.

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