Craig was born in Greenbriar County, West Virginia in 1807 and attended military school in Lewisburg, West Virginia. Allegedly, he left home after killing a man in self-defense and fled to St. Louis, Missouri in 1825. There, he met a group of French Canadian trappers and accompanied them to the upper Missouri River. He soon met a number of noted frontiersmen, including Milton and William Sublette, Jedediah Smith, Robert “Doc” Newell, and Joe Meek.
By 1829 he was in southeastern Idaho.
In 1832, he fought in the Battle of Pierre’s Hole, Idaho between the mountain men and a band of Gros Ventre Indians. He then worked for a while with explorer and soldier Captain Benjamin Benjamin Bonneville. He joined Joe Walker’s California Expedition of 1833-34.
In 1837, Craig, along with trappers, Pruett Sinclair and Philip Thompson established a trading post known as Fort Davy Crockett on the Green River in Brown’s Hole, Colorado. This had long been a favorite wintering place for Indians. In 1838 he took a Nez Perce wife named Pah-Tis-Sah, the daughter of Chief Thunder Eyes. Craig called his wife Isabel.
In 1840 Fort Davy Crockett was abandoned and the same year, Craig along with trapper friends, Robert Newell and Joe Meek, acted as guides to a missionary party to Fort Hall, Idaho, and on the Whitman Mission near Walla Walla, Washington. Newell and Meek, along with their families soon settled in the Willamette Valley of Oregon, but Craig joined his Nez Perce wife on the Nez Perce Reservation in Idaho where he established a farm near Lapwai.
At that time, the Reverend Henry Harmon Spalding was also at the reservations trying to Christianize the natives. Spalding was not pleased with William Craig’s arrival, writing in his diary: “I have seen enough of these mountain men already!” It would not get better, as the missionary worked fervently to strip the Nez Perce of their native ways, Craig led them in ignoring Spalding’s dogmatic ideals. However, Spaldin did find Craig useful and praised him as a hard worker. Craig provided refuge for Spalding’s wife and children in the panic after the 1847 Whitman Massacre.
In 1848, Craig was appointed as Indian Agent for the Nez Perce tribe and at Fort Boise. During this time he worked as an interpreter, peacemaker, and occasionally scouted for the army. He also served as a volunteer in the Yakima Indian War in Washington eventually attaining the rank of Lieutenant Colonel. The Treaty of 1855 granted to William Craig and his wife, Isabel, 640 acres of land in the Lapwai Valley, Idaho, then part of the newly formed Nez Perce reservation. He continued as an Indian agent until 1859. Afterward, he ran a hotel and stage stop on his farm.
He also owned a ferry across the Snake River in Lewiston, Idaho in 1861. He sold out in 1864 and over the years the ferry changed hands a number of times and operated until 1913.
William Craig died of a stroke on October 16, 1869. He and other members of his family are buried at the Jaques Spur Cemetery in Jacques, Idaho.