Cameahwait met Meriwether Lewis and three other members of the Lewis and Clark Expedition on August 13, 1805. He then accompanied Lewis across the Lemhi Pass to meet Clark. Sacagawea was with Clark's party, and recognized Cameahwait as her brother. To the Shoshoni Cameahwait and Sacagawea were brother and sister. In Shoshoni cousin and brother are the same word. This also means that they think of them as the same, so that during the translation when Sacagawea cried out that she recognized Cameahwait as her brother, that is what she meant, but whether they actually had the same father, let alone the same mother, is not clear. Cameahwait donated horses to Lewis and Clark to repay them for reuniting him with his long-lost sister. She had been kidnapped by the Hidatsa Indians when she was twelve years old. She and her friends Other Woman were used as slaves for the Hidatsas. They then sold the two Indian girls to Toussaint Charbonneau, a French-Canadian trapper. Charbonneau and Sacagawea both accompanied Lewis and Clark on their western expedition.
Cameahwait was killed during a battle with the Blackfeet at Bloody Creek in Montana, at an uncertain date. It is believed that he was buried on a butte between the towns of Lemhi and Tendoy, Idaho.
- Ambrose, S.E. (1996) Undaunted Courage ISBN 0-684-82697-6 pp.269-282
- Arrington, Leonard J. History of Idaho (University of Idaho Press: Moscow, Idaho, 1994) Vol 1, p. 515
- Mann, John (2004). Sacajawea's people: the Lemhi Shoshonis and the Salmon River country. p. 218. ISBN 978-0-8032-3241-9.