Rocannon's World (
1966) is the first novel by
Ursula K. Le Guin. As with all of her first three
novels, it was quite
short by modern standards and was published as one half of an
Ace Double. The book grew out of an earlier
short story "Semley's Necklace" and is set in the Ekumen or Hainish universe, as were most of Le Guin's early novels.
SPOILER ALERT: Plot spoilers below.
Briefly, the plot tells of Rocannon, the only survivor of a research party from a space-age society visiting a near-mediaeval planet. He believes his spaceship was destroyed by an enemy force and that this force will take over the planet. In classic planetary romance, he travels with brave natives and eventually saves them from the baddies. However, he is destined to live out his life on the heretofore nameless planet.
However, he does learn that (some) of the indigenes have telepathic powers - previously believed impossible in Rocannon's hi-tech society. This capacity is highly valued and leads to subsequent transformations in his original society.