Lewis and Clark along with Sacagawea play vital roles in the Louisiana Purchase.  Given challenges in Santo Domingo with trying to subdue slaves who would not acquiesce, France was willing to sell off the Louisiana Territory in North America.  In addition to this, Napoleon saw his position as seller as an opportunity to gain valuable cash to replenish his military as a result of his ongoing challenges with England.  The approximate 15 million dollars proved to be valuable and with this move, the size of the United States was nearly doubled.

Jefferson recognized that he had a sizable commitment to the growth of the nation.  The challenge was that he did not know exactly what he had purchased.  Thus, an expedition was needed.  Congress approved the expedition and Lewis and Clark set forth to explore the territory purchased.  The help that Sacagawea provided was invaluable.  Lewis and Clark benefited from her translation abilities as well as her knowledge of the territory.  While she was paid very little for her work, her contribution represented yet another moment in which Native Americans' assistance was not compatible with the compensation and recognition offered.  Sacagawea helped Lewis and Clark establish the American West as a path for many Americans to settle and establish as their own.