Ranulf de Briquessart

Ranulf de Briquessart (or Ranulf the Viscount) (died c. 1089 or soon after) was an 11th-century Norman magnate and viscount.

Ranulf's family were connected to the House of Normandy by marriage, and, besides Odo, bishop of Bayeux, was the most powerful magnate in the Bessin region. He married Margaret, daughter of Richard Goz, viscount of the Avranchin, whose son and successor Hugh d'Avranches became Earl of Chester in England c. 1070.

Ranulf is probably the "Ranulf the viscount" who witnessed a charter of William, Duke of Normandy, at Caen on 17 June 1066.

Ranulf helped preside over a judgement in the curia of King William (as duke) in 1076 in which a disputed mill was awarded to the Abbey of Mont St. Michael. On 14 July 1080 he witnessed a charter to the Abbey of Lessay (in the diocese of Coutances), another in the same year addressed to Remigius de Fécamp bishop of Lincoln in favour of the Abbey of Préaux. and one more in the same period, 1079 x 1082, to the Abbey of St Stephen of Caen. His name is attached to a memorandum in 1085, and on 24 April 1089 he witnessed a confirmation of Robert Curthose, Duke of Normandy and Count of Maine to St Mary of Bayeaux, where he appears below his son in the witness list.

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