Helliconia

The Helliconia trilogy is a series of science fiction books by British writer Brian W. Aldiss, set on the Earth-like planet Helliconia. It is an epic chronicling the rise and fall of a civilisation over thousands of years as the planet progresses through its incredibly long seasons, which last for centuries.

On Helliconia, there are two main intelligent species humans and Phagors. The humans are similar to Earth humans, although they evolved independently. The Phagors are white-furred humanoid beings, roughly the size of humans but with horned features resembling the mythical minotaur. They are intelligent, with their own language and culture, but their civilisation has never advanced beyond a hunter-gatherer level. Since the evolution of humans on the planet, the two species have been in constant conflict, with the phagors dominant during the great winter and the humans dominant during the great summer. Orbiting around the planet is a massive space station of Earth humans, the Avernus, and many probes and other monitoring devices, sending information about Helliconia to Earth.

The trilogy consists of the books Helliconia Spring (published in 1982), Helliconia Summer (1983), and Helliconia Winter (1985).