In 1299 April 20, W. Coventr. et Lych., Episcopus (Bishop Walter de Langton) was granted, by Edward I, (In year 27 of his reign) a Royal licence to crenellate Lichefeld (Lichfield Cathedral Close)

"procinctum domorum suarum et canonicorum infra lasusum Cathedral. Lichefeld. muro lapideo includere et murum illum kernellare"

Granted at Westminster, by King.

Grant of pavage for seven years with permission to build wall around precinct issued on 18 April; a more formal licence to crenellate the precinct granted of 20 April. The close was also licensed in 1348.

Original source is

• Calendar of Patent Rolls (1292-1301) p408, 409

(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;

• Thompson, M.W., 1998, Medieval bishops' houses in England and Wales (Aldershot: Ashgate Publishing) p167
  Greenslade, M.W. (ed), 1990, VCH Staffordshire Vol14 p60-1
  Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p77-9, 93
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p404

More details about licences to crenellate can be found here.

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