Foulques was the son of Giroir II de Beaupréau and Briccie de Chemillé. The date and place of his birth have not been found.
Foulques de Beaupréau
Giroir II de Beaupréau (-c1100)
Hamelin II de Beaupréau (1016->1062)
Josselin I de Rennes (->1028)
Briccie de Chemillé