Rainbow Mars, Engl. ed.

Blurb

Rainbow Mars is a science fiction short story collection by Larry Niven. It includes the five previously published Svetz stories and the eponymous main title novella, in which humans from Earth visit Mars and find it populated by the creations of Edgar Rice Burroughs, Ray Bradbury, C. S. Lewis, H. G. Wells, and Stanley G. Weinbaum. This means that Mars is inhabited by several different intelligent species and cultures. The story began as a collaboration with Terry Pratchett; a number of his ideas remain in the final draft, mainly the use of Yggdrasil.
The book collects a series of short stories by Niven, including "The Flight of the Horse", in which he introduced the Temporal Research Institute. The premise of the novel is that the old Secretary-General has recently died; his heir is more interested in extraterrestrials than the Earth beasts who went extinct due to excess pollution. This resulted in the Temporal Institute attempting to invent space flight, and several of its agents visiting Mars.
The starting temporal point is the year "+1108 Atomic Era," corresponding to 3053 AD in the Gregorian Calendar. The main character is Agent Hanville Svetz, a brave and resourceful man.