John de Bonvillars

Sir John de Bonvillars[1] (c. ?–1287) was a medieval Savoyard knight in the service of Edward I.

Knight of King Edward I's household and deputy Welsh Justicier to Otto de Grandson from 1284 to 1287.

[2] On 2 April 1277 he was bearer of a letter to Otto de Grandson who was besieging Dolforwyn Castle.

[3] First Constable of Harlech Castle from 1285 to his death by drowning (probably during siege of Dryslwyn in South Wales) between July and November 1287.

Married to Agnes de Bevillard (likely sister of Otto de Grandson) who held on to the Constable of Harlech role until succeeded by James of Saint George in 1290.