Louisiana Purchase and Lewis & Clark
Sacagawea (1787-1812) was a young Shoshone Indian woman who, while pregnant with her first child, accompanied the Lewis & Clark expedition on their journey to the Pacific. Traveling alongside her husband, an interpreter named Toussaint Charbonneau, Sacagawea was the only Indian member of the Corps of Discovery and its only woman.
Sacagawea proved instrumental to the journey's success. At the expedition's darkest hour—stranded high in the Rocky Mountains without guides or horses—Lewis and Clark encountered a band of Shoshone Indians led by Cameahwait, who surprisingly turned out to be Sacagawea's long-lost brother. (Sacagawea had been kidnapped as a child and taken far away from her people.) With Cameahwait's help, the Corps of Discovery survived the mountain crossing and progressed to the Pacific.