In Henry IV Part 1, Owen Glendover, the leader of the Welsh rebels joins the insurrection against King Henry. Glendower, a man steeped in the traditional lore of Wales, claims to command great magic. Therefore, mysterious and superstitious, he sometimes acts in response to prophecies and omens. In the play, Glendover boasts to Hotspur, “I can call the spirits from the vastly deep.” Hotspur deflates Gelendover with, “Why, so can I or so can any man; But will they come when you call them?”