Sacagawea was the daughter of a Shoshone chief. She was kidnapped by a Hidatsa war party at about age 12 and sold to a fur trader. She was the only woman on Louis and Clark's expedition to the Louisiana Purchase territory.
Another woman in Wyoming may have been named Sacajawea, but Louis and Clark's records spelled this Sacagawea's name with a "g." She was born in what is Idaho today and lived with the Hidatsa in what became North Dakota.
Toussaint Charbonneau, the fur trader who bought her, made her one of his two wives. Louis and Clark chose them to accompany the expedition as interpreters. Sacagawea knew Shoshone and Hidatsa, Charbonneau knew Hidatsa and French, and a member of the expedition corps could translate from French to English.
Having her with the travelers signaled to other Indian tribes that the group was not a war party. Sacagawea interpreted and guided them through Shoshone land. The chief turned out to be her brother, so she was able to get horses from him for the expedition.
Sacagawea managed to see the Pacific Ocean and a whale before returning home. She died while still in her 20s.