In 1369 April 24, Abbas et Conventus de Waltham Sanctae Crucis (Abbot Thomas de Wolmersty) was granted, by Edward III, (In year 43 of his reign) a Royal licence to crenellate Waltham Sanctae Crucis (Waltham Abbey)

"mansum Abbatiae et procinctum ejusdem"

Granted at Westminster, by privy seal.

A licence to crenellate the belfry of the abbey, then ruinous, had been granted in 1366 (qv). This one, to crenellate the abbot's house and precinct, may represent a more nervous clergy becoming aware of an upsurgent and anti-clerical populous, in an area where such feelings were particularly strong.

Original source is

• Calendar of Patent Rolls (1367-70) p245

(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;

• Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p94
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p417

Abbot Thomas de Wolmersty, elected 1345, (d.1371)

More details about licences to crenellate can be found here.

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