Sacagawea is one of O'Dell's strong female characters who consistently behaves with nobility and integrity. Best known in history for her importance as a guide and interpreter for the Lewis and Clark expedition, Sacagawea's story, as told by O'Dell, shows the strength she possessed in surviving the hardships of exploring an unknown territory and in overcoming personal disappointments to raise her son in the Shoshone manner. As Sacagawea comes to love Captain Clark, she refuses to be blinded to her greatest responsibility—her son Meeko. It is that responsibility that eventually spurs her to return to her native people and raise her son in the Shoshone traditions.

The other characters in the novel all serve in some degree as a contrast to Sacagawea. Charbonneau is pictured as a greedy and selfish fool. His abuse of Sacagawea is evidence of his cruel and uncaring...