Joseph Reddeford Walker looms large in the lore of the early West. From the Missouri to the San Joaquin, from the Gila to the Yellowstone, Walker spent more than thirty years—from the 1830s to the Civil War—trapping beaver in the Rockies, bartering with the Crow, Ute, Cheyenne, Arapahoe, and Shoshone Indians, droving cattle and horses, and guiding emigrants and explorers. Walker was associated with Captain Bonneville in the fur trade from 1832 to 1835, but we have only an incomplete account these years in Washington Irving’s, The Adventures of Captain Bonneville and Zenas Leonards, Narrative. But the twist of fate that threw Daniel Ellis Conner into Walker’s party, en route from Colorado to explore Arizona in 1861, affords us several hundred manuscript pages, Conner’s four-year travel diary, relating his hair-raising adventures with this great mountain man. Joseph Reddeford Walker and the Arizona Adventure offers a superb chapter in the history of the West. Included are tales of the early Apache wars in New Mexico and Arizona; “The Betrayal of Mangas Coloradas,” with Conner’s eyewitness account of the Apache chief’s death; the emigrant trains to California; early settlement; mining operations, in “The Perils of Prospecting,” and countless episodes of action and violence that make fictional accounts pale in comparison. Donald J. Berthrong  (1922 – 2012) was Professor of History, Purdue University, and is author of  The Southern Cheyennes  and  The Cheyenne and Arapaho Ordeal: Reservation and Agency Life in the Indian Territory, 1875–1907 .