In 1345 Nov 9, Prior et fratres ordinis Sancti Augustini de Salop was supposedly granted, by Edward III, (In year 19 of his reign) a Royal licence to crenellate Sancti Augustini de Salop (St Augustines, Shrewsbury)

"quendam murum lapideum extra villam predictam una cum duabus turribus rotunis superedificatis et una domo kernellata desuper eundem murum constructa, muro ejusdem villae adjunctum, &c. ad elargationem mansi,
The prior and Austin Friars of Shrewsbury have made petition to the king that, whereas by inquisition taken by Thomas de Swynerton, escheator in the county of Salop, it is found that it is not to the damage of the town if he assign in mortmain to them a stone wall without the town with two round towers built on it and a crenellated house along the wall adjoining the wall of the town, as well as a plot of land by the same wall containing 20 perches of land in length, and part of the same con- tains 2 perches in breadth without the town adjacent to the water of Severn there, for the enlargement of their manse, he will do this, and he has assented to their petition."

Granted at Westminster, by privy seal.

Although this document has been considered by some as a licence to crenellate the current opinion rejects this as a licence to crenellate.

In Turner and Parker as a licence to crenellate. The licence to crenellate allegedly issued in 1345 was in fact a mortmain grant. However, in 1337 the friars were granted a stone wall extending from the priory to the river on condition 'that they built a substantial embattled house there'. In 1342 mention is made of 'a certain crenellated house constructed upon the aforesaid wall'.

Original source is

• Calendar of Patent Rolls (1345-48) p11

(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 p92n18
  Jackson, M.J.,1988, Castles of Shropshire (Shrewsbury: Shropshire Libraries) p73 [reject]
  Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p96n8 [reject]
  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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