God Emperor of Dune

God Emperor of Dune is a science fiction novel by the American writer Frank Herbert, published in 1981 and the fourth in his Dune series of six novels. It was ranked by Publishers Weekly as the eleventh hardcover fiction bestseller of 1981.

The situation is given in the title and the premise. Leto II Atreides has ruled the universe as a tyrant for three thousand five hundred years after becoming a hybrid of human and sandworm, and the terraforming of Arrakis has killed all the other sandworms, which leaves his control of the remaining spice as the foundation of his authority. He retains only his human mind inside a worm's body. Leto is the son of Paul Atreides, and what he has traded away is his human form rather than his mind.

Because the novel sits thousands of years after the first three books, it depends on the reader's knowledge of what the earlier volumes established and on accepting a protagonist who is no longer human in form. The novel takes place three thousand five hundred years after the original trilogy, so the reader's knowledge of the earlier books is doing a great deal of the work.