In 1345 Feb 12, Willielmus de Clynton, Comes Huntyngdon (William de Clinton, earl of Huntingdon for the use of his nephew John de Clynton) was granted, by Edward III, (In year 19 of his reign) a Royal licence to crenellate Maxstok (Maxstoke Castle)

"quoddam mansum ad opus delecti nobis Johannis de Clynton, nepotis ejusdem Comitis"

Granted at Westminster, by privy seal.

King writes "Not apparently begun at this time. [1345]" but other authorites seem to have little problem with this being the date of the initial castle works.

Original source is

• Calendar of Patent Rolls (1343-45) p444

(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;

• King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p488n22
  Salzman, L.F. (ed), 1947, VCH Warwickshire Vol4 p133-6
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p414

More details about licences to crenellate can be found here.

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