In 1315 Oct 6, Rogerus de Swynnerton (Sir Roger Swynnerton) was granted, by Edward II, (In year 9 of his reign) a Royal licence to crenellate Swynnerton (Swynnerton)

"Licence to Roger de Swynnerton to crenellate his dwelling-place (mansum) of Swynnerton. co. Stafford."

Granted at Walsingham, by King, on the information of R. de Northburgh.

Original source is

• Calendar of Patent Rolls (1313-17) p356

(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 source are;

• Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p407

Roger Swynnerton (1285-1338)

A courtier under Edward II, although was a notable beneficiary of Edward III in 1331 when he was granted large amounts of Despenser lands in Staffordshire and Cheshire.
(said to be underage) 1299 [SHC 1886 ii 60-1]; (knighted) a1306; (on first Dunstable Tournament armorial roll) *1309; (presented at Swynnerton) 1312 & 1322 & ?1330 &1334; (lord of Swynnerton) *1316; (Constable, Tower of London) 1321-3; (as a Staffs Knight, summoned to attend the King at Westminster and on an armorial roll) *1324; (J.P., Staffs) 6 Sep 1336-death; (summoned to Parliament as a Baron) 23 Apr 1337; (M.P., Staffs) [summons only] 18 Aug 1337.
Roger Northburgh, later to become bishop of Lichfield, was Lord Privy Seal in 1315.

More details about licences to crenellate can be found here.

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