The Hainish Cycle consists of a number of science fiction novels and stories by Ursula K. Le Guin. It is set in a future history in which civilizations of human beings on planets orbiting a number of nearby stars, including Terra ("Earth"), are contacting each other for the first time and establishing diplomatic relations, and setting up a confederacy under the guidance of the oldest of the human worlds, peaceful Hain. In this history, human beings did not evolve on Earth but were the result of interstellar colonies planted by Hain long ago, which was followed by a long period when interstellar travel ceased. Some of the races have new genetic traits, a result of ancient Hainish experiments in genetic engineering, including people who can dream while awake, and a world of hermaphroditic people who only come into active sexuality once a month, not knowing which sex will manifest in them. In keeping with Le Guin's style, she uses varied social and environmental settings to explore the anthropological and sociological outcomes of human evolution in those diverse environments.
The Hainish novels The Left Hand of Darkness (1969) and The Dispossessed (1974) have won literary awards, as have the novella The Word for World Is Forest (1972) and the short stories "The Day Before the Revolution" (1974) and "The Matter of Seggri" (1994).
Le Guin herself often discounted the characterization of a "Hainish Cycle", writing on her website that "The thing is, they aren't a cycle or a saga. They do not form a coherent history. There are some clear connections among them, yes, but also some extremely murky ones."[1][2]