One of Thomas Jefferson’s greatest achievements was the Louisiana Purchase, in which the United States acquired 828,800 square miles of the French territory La Louisiane in 1803. Encompassing all or part of 14 current U.S. states, the land included all of present-day Arkansas, Missouri, Iowa, Oklahoma, Kansas, and Nebraska; parts of Minnesota that were west of the Mississippi River; most of North Dakota; nearly all of South Dakota; northeastern New Mexico; portions of Montana, Wyoming, and Colorado east of the Continental Divide; and Louisiana west of the Mississippi River. Today, the land included in the purchase makes up approximately 23 percent of the territory of the United States.
French and Spanish Ownership
At the end of the French and Indian War in 1763, France lost all of its possessions in North America, dashing hopes of a colonial empire. This empire was centered on the Caribbean island of Santo Domingo and its lucrative cash crop of sugar. (“Santo Domingo” is an old name for the island of Hispaniola, where the modern countries Dominican Republic and Haiti are located.)The French territory called La Louisiane, extending from New Orleans up the Missouri River to modern-day Montana, was intended as a granary for this empire and produced flour, salt, lumber, and food for the sugar islands. By the terms of the 1763 Treaty of Fontainebleau, however, Louisiana west of the Mississippi River was ceded to Spain, while the victorious British received the eastern portion of the huge colony.
