This article compares the experiences of missionaries and mountain men in the early years (1825-1848) of US occupancy of the "Oregon Country," which included today's Idaho. For very different reasons, both the Whitmans and Jedediah S. Smith entered the pantheon of 19th century American iconic "heros," but their real lives were more complex and ambiguous than the mythology suggests. This article explains and analyzes the myths and realities surrounding Marcus and Narcissa Whitman, and Jedediah S. Smith. For a sample, read the following introductory paragraph: Dateline: The Cimarron River near the Kansas-New Mexico border, May 1831 A lone horseman, his sun-bronzed face ravaged by deep scars, is seeking desperately needed water for parched men and livestock. His suffering companions lag a few miles behind him, in a traders' caravan crawling across the "water scrape" toward Sante Fe under a mercilessly hot and brazen sky. Halting at a water hole close by the Cimarron River, the rider suddenly realizes that he is not alone. Several Comanche warriors have appeared out of nowhere. This man, having already survived a perilous decade as a mountain man, senses that he is done for, but he is ready, as the contemporary phrase went, to "sell his life dearly." As nervous horses snort and shuffle, a Comanche shoots him in the chest. The man fires his rifle, killing one of the leaders. He grasps for his pistols, but other Comanches fire their guns and he tumbles from his horse. The Indians gather up a few of the dead man's belongings and hit the trail. Some comancheros--Hispanic men who trade with Comanches--later bring some of the man's belongings and a few details of the encounter to Santa Fe. The man's body is never recovered. That brief, bloody moment snuffed out the spectacular career of a trapper and explorer named Jedidiah Strong Smith. Few men roamed--and none mapped--more of the early West than Smith.