In 1316 Nov 17, Johannes de Cherleton (John, Lord Charlton) was granted, by Edward II, (In year 10 of his reign) a Royal licence to crenellate Cherleton (Charlton Castle)

"Licence to John de Cherleton (mansum suum) to crenellate his dwelling-place of Cherleton, co. Salop."

Granted at York, by King.

John Cherleton is called Master on the next licence, for which he gives information, he was summoned to parliament in 1313 as Lord Charlton of Powis.

Original source is

• Calendar of Patent Rolls (1313-17) p566

(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;

• Baugh, G.C. (ed), 1985, VCH Shropshire Vol11 p312
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p439n103
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p407

More details about licences to crenellate can be found here.

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