In 1335 Feb 3, Johannes de Heslarton (John Heslerton) was granted, by Edward III, (In year 9 of his reign) a Royal licence to crenellate Wilton in Pykerynglith (Wilton Hall near Pickering)

"Licence for John de Heslarton to crenellate his dwelling-place (mansum) at Wilton in Pykerynglith, co. York."

Granted at Roxburgh, by privy seal.

The ownership of the manor was disputed in 1293 and it was conveyed to John after this date. It was then, in 1309, siezed by Gerard Salvayn, serving as escheator north of the Trent, and only returned after parliamentary action (King pp. 37-9) so licence possibly about confirming ownership with the new king's regime.

Original source is

• Calendar of Patent Rolls (1334-38) p88

(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. Licentia is best translated as 'freedom to' not 'permission'.)

Significant later source are;

• King, Andy, 2000, 'Thomas of Lancaster's First Quarrel with Edward II' in Ormrod, Mark (ed), Fourteenth Century England III (Woodbridge: Boydell and Brewer)
  Emery, Anthony, 1996, Greater Medieval Houses Vol1 (Cambridge) p421
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p410

John Heslerton

Had made a collegiate church at Lowthorpe in 1333, where possibly his tomb can still be seen.
Called knight when recorded as witness to an inspeximus of an indenture in 1330 (CPR 1330-4 p. 172)

More details about licences to crenellate can be found here.

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