William H. Ashley's expedition up the Missouri River in 1822 met with misfortunes that forced far-reaching changes in the fur-trading operations of the West. His claim to fame as an entrepreneur and explorer is clear in The Explorations of William H. Ashley and Jedediah Smith. Just as vivid is the story of the Bible-quoting Jedediah Smith, a member of Ashley's original expedition, who branched off into little-known regions, becoming the first American to reach California by an overland route. In his introduction, James P. Ronda supplies the historical context for their explorations. A professor of history at the University of Tulsa, he is the author of Lewis and Clark among the Indians (1984) and Astoria and Empire (1990).