In 1341 May 3, Robertus de Maners (Robert Manners) was granted, by Edward III, (In year 15 of his reign) a Royal licence to crenellate Echale [Othale] [Ethale] (Etal Castle)

"mansum suum de Ethate"

Granted at Westminster, by privy seal.

In 1341 Edward III granted the lord of Etal, Robert Manners, licence to crenellate. Parker gives name on licence as Echale; King gives it is as Othale. Bates as Ethale

Original source is

• Calendar of Patent Rolls (1340-43) p179 [Othale]

(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;

• Emery, Anthony, 1996, Greater Medieval Houses Vol1 (Cambridge) p159
  King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p367n117
  Bates, C.J., 1891, Border Holds of Northumberland (London and Newcastle: Andrew Reid) p9
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p413

More details about licences to crenellate can be found here.

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