The Gatehouse website record of a licence to crenellate for Portland [Rufus Castle] granted on 1257 Dec 12

Licence for Aymer, {bishop} elect of Winchester, the king's brother, to strengthen the island of Portand, with stone and lime and to crenellate it like a castle, as he shall think most expedient.
By K. in the presence of Edward his son, Henry son of the king of Almain, William de Valencia, John Maunsell, Hugh Bigod, Philip Lovel, Robert Walerand and others, and Peter de Monte Forti. (CPR)

Adomar Winton. electus possit kernellare ... insulam de ... Portland. (Turner and Parker)

Granted at Westminster. Grant by King.

Comments

King writes "to Aylmer de Lusignan, Bishop-elect of Winchester. The terms of this licence are extremely vague; Aylmer was permitted to crenellate the island or make a castle there at his complete discretion. The nature of the problem seems not to have been considered at this stage."

It is generally presumed that Rufus castle is the site of any work that may have resulted from this licence. King' s 'problem' seems to be an assumption the whole island was intended to be fortified.

Original source is;

Lyte, H.C. Maxwell (ed), 1908, Calendar of Patent Rolls (1247-58) p. 607 online copy

(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 sources are;

Thompson, M.W., 1998, Medieval bishops' houses in England and Wales (Aldershot: Ashgate Publishing) p. 167
Coulson, C., 1994, 'Freedom to Crenellate by Licence - An Historiographical Revision' Nottingham Medieval Studies Vol. 38 p. 131
King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol. 1 p. 132n32
Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol. 3 part 2 p. 402 online copy

Lusignan (Valence), Aymer de (c.1228–1260), bishop of Winchester

Lusignan (Valence), Aymer de (c.1228–1260), bishop of Winchester, was one of the younger sons of Hugues (X), count of La Marche, and his wife, Isabella of Angoulême (d. 1246), the widow of King John. Given many favours by his half brother Henry III. Destined for a career in the church. He was a controversal figure, quarrellsome and quick to incite his followers to use violence to 'resolve' disputes. If any individual would need a strong, well defended, retreat it would be Lusignan but the location, on the south coast, is probably of more significance, in this regard, since his real defence, in case of attack, would be to sail to his estates in Poitou. The obtaining of the Portland, by Lusignan, in speculative land markets meant the licence probably had more to do with confirming ownership of the land and reconfirming his position as a royal favourite.

Biographical source include;

Nicholas Vincent, Sept 2004, ‘Lusignan , Aymer de (c.1228–1260)’ Oxford Dictionary of National Biography (Oxford University Press) online edn, Jan 2008 online copy (subscription may be needed)
Ridgeway, H.W., 1989, 'Foreign Favourites and Henry III's Problems of Patronage, 1247-1258' The English Historical Review Vol. 104 No. 412. p. 590-610

More information about licences to crenellate can be found here.

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