In 1262 Feb 5, Roger de Sancto Johanne (Roger de St. John) was granted, by Henry III, (In year 46 of his reign) a Royal licence to crenellate Lageham in Walkested (Lagham Manor)

"to fortify (firmare) his house of Lageham in Walkested with a dyke, stockades (brethachiis) and a paling; and for his heirs to keep it so, so long as they are faithful to the king."

Granted at Westminster,

licensed for dyke, stockades and paling. The express condition of loyalty is exceptional for an English licence.

Original source is

• Calendar of Patent Rolls (1258-66) p199

(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) Vol2 p467n17
  Coulson, C., 1979, 'Structural Symbolism in Medieval Castle Architecture' Journal of the British Archaeological Association Vol132 p84n40
  Malden, H.E. (ed), 1912, 'Parishes: Godstone' VCH Surrey Vol4 p402

More details about licences to crenellate can be found here.

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