"Licence, by advice of the council, for Humphrey, duke of Gloucester, and Eleanor his wife, to impark 200 acres of land, pasture, wood, heath and furze at Estgrenewich, which are outside the forest, notwithstanding that 17 acres of the said pasture, heath and furze have been granted to the said duke and duchess, in exchange for other lands, by the prior and convent of the house of Jesus of Bethlehem, Shene, having formed part of the manor of Estgrenewich, with which the said duke and duchess to enclose their manor house and mansion of Estgrenewich with walls, to crenellate the same, and to build a tower of stone and mortar in the park."
Granted at Westminster, by privy seal.
A further licence, granted by petition in Parliament is granted for 'Grenewych' in 1437. Apart from the differences in name this has very similar wording and would appear to be for the same building, or possibly a different building in the same complex. Coulson (1995) list this as a, suburban town house. I consider it a ordinary country manor close to London.
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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