• Born: Abt 1224, Brabant, Antwerp, Beligium
• Married (1): 14 Jun 1237, Compiègne, Oise, France
• Married (2): 31 May 1254
• Died: 29 Sep 1288

  Research Notes:

The Oude Kronik van Brabant names (in order) "Mechtildim comitissam Atrebatensem et Sancti Pauli, Mariam comitissam palatinam Reni, Beatricem lantgraviam Thuringie postea comitissam Flandrie, et Margaretam sanctiomonialem, postea abbatissam in Valle Ducis" as the daughters of "Henricus secundus et quintus dux Brabancie" and his first wife Marie. The Genealogia Ducum Brabantiæ Heredum Franciæ names "Machtildis" as oldest of the four daughters of "Henricus…secundus dux" and his wife Maria, and her first husband "Roberto comitis Attrebatensi, filio Regis Francie", their children "Robertum comitem Attrebatensem et unam filiam", and her second husband "comiti Sancti Pauli" referring to, but not naming, their sons and daughters.

The Chronicle of Alberic de Trois-Fontaines records the marriage "apud Conpendium in octavis Pentecostes" of "Francie frater regis Robertus" and "Mathilde filia ducis Brabantie". The Chronicle of Guillaume de Nangis records the marriage in 1238 "apud Compendium" of "sanctus Ludovicus rex Franciæ Robertum fratrum suum" and "filiæ ducis Brabantiæ Mathildi". The late 13th century genealogy by Balduinus de Avennis records that "Johannes…fratri Guidoni [comes] Sancti Pauli" married "Macthildem filiam Henrici ducis Brabantiæ, relictam comitis Atrebatensis Roberti". ¹