Ermengarde, or Irmengarde de Hesbaye (born about 778) was the daughter of Ingerman, Count of Hesbania (Hesbaye, now in Liège, Belgium) and Hedwig of Bavaria.
Her paternal grandfather Gunderland, Count of Hesbania was himself a son of Sigrand, Count of Hesbania and Landrade of Austrasia. Landrade was reportedly daughter of Charles Martel by either Chrotrud or Swanachild .
Ermengarde married in 794/795 Louis the Pious, king of Aquitania, king of Franks, king of Italy, ruler of the Holy Roman Empire.
She had six children :
- Lothair I, born 795 in Altdorf, Bavaria
- Pepin of Aquitaine , born 797
- Adelaide, born. ca. 799. Possible wife of Robert the Strong, possible mother of Odo, Count of Paris and Robert I of France.
- Rotrude, born 800.
- Hildegard / Matilda, born ca. 802. Wife of Gerard, Count of Auvergne , possible mother of Ranulf I of Poitiers.
- Louis the German, born ca. 805.
She died at Angers, France on 3 October, 818. Louis was married to Judith of Bavaria a few years later and became father of Charles the Bald.
