Hippolyte Delehaye was a Belgian Jesuit and a hagiographical scholar, as well as a member of the Society of Bollandists. He became president of the society in 1912. His research was focused on gathering and evaluating historical documentary sources regarding the life and cult of Christian Saints. He was an editor of the Bibliotheca Hagiographica Graeca in 1895 and of the journal Analecta Bollandiana. He published four books including Les Légendes hagiographiques and Les Origines de culte des martyrs.