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.