He trapped with the Sublettes (William and Milton) and Jedediah Smith in the Blackfoot country until he joined Joseph R. Walker's California Expedition of 1833–34.
In 1836, William Craig, Pruett Sinclair and Philip Thompson [2] established a trading post known as Fort Davy Crockett in Brown's Hole, now in the state of Colorado.
While Newell and Meek and their native wives and children sought a new life in the Willamette Valley of what is now Oregon, Craig joined his Nimiipuu family along the Clearwater River and Lapwai Creek of what is now Idaho.
According to a later affidavit,[3] Craig had, in 1838, married Pahtissah (he renamed her Isabel), a Nez Perce woman who was the daughter of Hin-mah-tute-ke-kaikt also known as Thunder Eyes.
The Treaty of 1855 granted to William Craig and his wife, Isabel, 640 acres of land in the Lapwai Valley, then part of the newly formed Nez Perce reservation.