Geoffrey II, de Château-Landon (died 1043–46) was the Count of Gâtinais. He was the son of Hugues du Perche, Count of Gâtinais, by Béatrice de Mâcon, the daughter of Aubry II de Mâcon. About 1035 he married Ermengarde of Anjou, Duchess of Burgundy, daughter of Fulk III, Count of Anjou. After Geoffrey's death she married secondly Robert I, Duke of Burgundy.
Together, Geoffrey and Ermengarde had:
- Hildegarde de Château-Landon, married c.1060 to Joscelin I, Lord of Courtenay; his famous son was Joscelin I, Count of Edessa by a different wife.
- Geoffrey III (1040 - 1096)
- Fulk IV (1043 - 1109)
- John Burke & Sir Bernard Burke, C.B., Burke's Peerage, Baronetage, and Knightage, Edited by Peter Townsend (Burke's Peerage Ltd.,London, 1963)p. xciii
- Detlev Schwennicke, Europäische Stammtafeln: Stammtafeln zur Geschichte der Europäischen Staaten, Neue Folge, Band II (Marburg, Germany: J. A. Stargardt, 1984), Tafel 82
- Kate Norgate, England Under the Angevin Kings, Vol. I (Macmillan and Co., London, New York, 1887), p. 250
- Jim Bradbury, 'Fulk le Réchin and the Origin of the Plantagenets', Studies in Medieval History Presented to R. Allen Brown, Ed. Christopher Harper-Bill, Christopher J. Holdsworth, Janet L. Nelson (The Boydell Press, 1989), p. 27