"Licence, with the assent of the council, for the king's lieges lately dwelling at Plymmouth within the towns of Sutton Vautort and Sutton Priour to fortify these towns and the port of Plymmouth with a wall of stone and lime and make and crenellate fortalices, towers and other defences there for the defence of the same and the adjoining country."
Granted at Westminster, by privy seal.
Single grant of murage in 1378 may not have resulted in much work, but town given large grants of money in 1463 and 1485. A licence to crenellate was granted to 'the King's lieges lately dwelling at Plymouth' in 1404 followed a few days later (12 Feb 1404) by a Commission empowered "to take stone-cutters, carpenters and other artificers for the fortification of the town of Plymmouth and the port there with a wall of stone and lime and the making and crenellation of fortalices,towers and other defence."
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;
More details about licences to crenellate can be found here.
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