ERMENGARDE de Tonnerre ([1023/26]-before 1090). "Rainaldus comes" donated property to the monastery of Saint-Michel, for the soul of "filii mei Othonis" buried in the monastery and "uxore mea Herviz…filio nostro Arduyno ac filia Ermengarda", by charter dated Jul 1036[2715]. Her birth date is estimated from her marriage in [1039], combined with the fact that she was still not of marriageable age in 1036. "Raynardus comes" donated property to the monastery of Saint-Michel (on his deathbed), with the consent of "uxoris mee Herviz et filii mei Harduini sive filie mee Ermengarde", by charter dated 16 Jul 1039 which also names "mater mea Ermengardis"[2716]. Her marriage is referred to in the Gesta pontificum[2717]. She succeeded as Ctss de Tonnerre in 1065 when her cousin Comte Hugues-Rainard became bishop of Langres[2718]. m ([1039]) as his first wife, GUILLAUME [I] Comte de Nevers et d'Auxerre, son of RENAUD [I] Comte de Nevers & his wife Hedwig [Avoie] de France [Capet] (-20 Jun 1098, bur Nevers Saint-Etienne). Comte de Tonnerre 1065.