In 1252-3, communes Norwici was supposedly granted, by Henry III, (In year 37 of his reign) a Royal licence to crenellate Norwici (Norwich City Wall)

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

King writes "Dugdale, Mon., iv, 14; habuerunt licenciam communes Norwici includendi eandem villam cum fossis. The Chronicle quoted here dates this to 37 Hen. III (i.e. 1252-3) and also to A.D. 1209, but as we are also told told that this occured 60 years after an event in 1194, it is likely that the regnal year gives the correct reading, more or less." This is not a licence to crenellate, although a royal licence to enclose the town with a ditch has a similar quality (some ditches, possible originally of saxon date, may have alreaddy existed.)

Original source is

• Cartulary of Binham Priory (Not in Royal Rolls)

(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;

• King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol2 p313n27
  Turner, H.L., 1971, Town Defences in England and Wales (London) p136
  Dugdale, William [Caley, J., Ellis, H. and Bandinel, B. (eds)], 1817-30, Monasticon Anglicanum (London) Vol4 p14 http://monasticmatrix.org/MatrixBooks/Dugdale/Volume4/Dugdale-Monasticon%20(Vol.%204%20Part%2002%20Norwich).pdf

More details about licences to crenellate can be found here.

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