In 1146, Rannulfum comitem Cestr (Earl Rannulph of Chester) was supposedly granted, by Stephen, a Royal licence to crenellate tower in Lincoln Castle (Lincoln Castle)

"Quo facto idem rex concessit firmare unam de turribus suis de castro Lincoln(ie) de qua comes habebit dominium"

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

An agreement was made, following the war of the Anarchy, for Earl Ranulf to hold a certain tower, previously fortified by the Countess Lucy. Not, in a meaningful sense, a licence to crenellate although has been called this by some.

Original source is

• Regesta Regum Anglo-Normannorum Vol3 p64-5

(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;

• Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p95n2

More details about licences to crenellate can be found here.

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