**Four award-winning authors. Four amazing alternate histories.** In this collection of novellas, four masters of alternate history turn back time, twisting the facts with four excursions into what might have been. Bestselling author Harry Turtledove imagines a different fate for Socrates (now Sokrates); S. M. Stirling envisions life in the wilds of a re-barbarized Texas after asteroids strike the earth in the 19th century; Sidewise winner Mary Gentle contributes a story of love (and pigs) set in the mid-15th century, as European mercenaries prepare to sack a Gothic Carthage; and Nebula nominee Walter Jon Williams pens a tale of Nietzsche intervening in the gunfight at the O.K. Corral.