Question: Who is Hugh De Courtenay, 1St/9Th Earl Of Devon's paternal grandfather?
Sentence (from "Hugh de Courtenay"): Sir Hugh de Courtenay (1251–1292) was the son and heir of John de Courtenay, feudal baron of Okehampton, Devon, by Isabel de Vere, daughter of Hugh de Vere, 4th Earl of Oxford.
Relevant evidence: Yes