"Mandate to make letters to Robert ... that he may crenellate his castles of Brouham and Pendragon, C. Westmoreland."
Granted at Langley,
The enrollment, the the Chancery Warrents, is mutilated.
Original source is
(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;
A leading baron and, briefly, marshal of England, most notable for his military service against the Scots. Killed, leading a charge, at the battle of Bannockburn. Given his service and it is perhaps surprising he was not ennobled. His relationship with Edward II was uneasy and he disapproved of Piers Gaverston but his qualities and reputations as a soldier made him someone the king could not afford to entirely alienate.
In the years around 1300, possibly as a result of a visit in that year by Edward I and his court, Clifford made substantial additions to Brougham Castle, finally gaining the seal of royal approval in the form of a licence to crenellate in 1309. (Summerson)
Biographical source include;
More details about licences to crenellate can be found here.
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