MATHIEU [III] de Montmorency (-after Apr 1270). Seigneur de Montmorency. "Mathei domini de Montemorenciaco et dominæ Ioannæ eius uxoris" confirmed donations to Ponthieu Saint-Martin by charter dated 1250[682]. A charter dated May 1260 records an agreement between Saint-Denis and "mon seigneur Mahiu de Mommenci chevalier...et Thibaut son frere et damoisele Aales et damoisele Iehenne ses sereurs"[683]. "Matheus dominus Montismorenciaci et Iohanna eius uxor" sold property to Montmorency Saint-Martin by charter dated Apr 1270[684]. m (before 1250) JEANNE de Brienne, daughter of ERARD [II] de Brienne Seigneur de Ramerupt & his second wife Philippa de Champagne (-[1 Aug], 1270 or after). A manuscript history of the abbey of la Piété de Rameru, when naming the daughters of Erard de Brienne, records "Damoisele Iehanne qui puis fu Dame de Montmoranci", the passage indicating that her marriage took place after the death of her father[685]. "Mathei domini de Montemorenciaco et dominæ Ioannæ eius uxoris" confirmed donations to Ponthieu Saint-Martin by charter dated 1250[686]. "Matheus dominus Montismorenciaci et Iohanna eius uxor" sold property to Montmorency Saint-Martin by charter dated Apr 1270[687]. The necrology of Rameru La Piété records "Kal Aug...Iohanna domina de Montemorencii et Matheus vir eius”[688]. The joint reference to husband and wife suggest that this entry may relate to a joint donation in addition to or instead of the decease of either party. Mathieu [III] & his wife had children