In 1298 Aug 21, Johannes de Cadamo (M. John of Caen) was granted, by Edward I, (In year 26 of his reign) a Royal licence to crenellate domos suas quas habet infra clausum Ebor. ecclesi (John of Caen House, York Cathedral Close)

"domos suas quas habet infra clausum Ebor. ecclesi"

Granted at Linton Roderick, by privy seal.

Original source is

• Calendar of Patent Rolls (1292-1301) p358

(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., 1995, 'Battlements and the Bourgeoisie: Municipal Status and the Apparatus of Urban Defence' in Church, Stephen (ed), Medieval Knighthood Vol. 5 (Boydell) p165n189
  Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p93
  Cheney, C.R., 1972, Notaries Public in England (Oxford), esp. p. 21 n. 4 and pp. 142-51.
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p404

John of Caen

M. John of Caen. He is called 'Johannes Erturi [son of Arthur] de Cadamo'. Although his family derived from Caen, he prob. belonged to a branch living in England. - Apostolic notary, first occ. in connection with York 15 Oct. 1268 (Reg. Giffard p. 142). Royal clerk 1276-1310 (Cheney, Notaries Public, as below n. 156). First occ. as can. 1288 (Foedera I (2) 698). Claimed this preb. against Berard of Naples on strength of prov. by pope John XXI (Sept. 1276 -May 1277) and royal patronage; evidently in possession of preb.; his surrender of the fruits ordered by pope 22 Apr. 1289 (ibid. p. 707). Occ. as this preb. 11 Dec. 1295 (CPR 1292-1301 p. 215). Scrutator at el. of abp. Corbridge, before 9 March 1300 (CPL I 586 = Reg. Bon. VIII no. 3475), and at el. after d. of Corbridge on 22 Sept. 1304 (CPL II 8). Had houses in Goodramgate, York, 22 July 1298 (Chs. Vicars Choral no. 163) and in Minster Close 21 Aug. 1298 (CPR 1292-1301 p. 358). Also dean of Stafford from 28 Oct. 1294 (ibid. p. 106); can. of Wells, his preb. vacant 9 Apr. 1310 (2 Fasti VIII 81). Exch. this preb. with William Melton for preb. in church of Darlington before 23 March 1310 (Reg. Greenfield IV 102, 318). (Greenaway)

Biographical source include;

• Greenaway, Diane, 1999, Fasti Ecclesiae Anglicanae 1066-1300 Vol6 p68
  

More details about licences to crenellate can be found here.

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