How the United States Laid Claim to the Mississippi River, One Mile at a Time

On October 27, 1815, Prospect Robbins arrived by boat at the point in the alluvial swamps where the Arkansas and Mississippi rivers meet. He planted a post in the ground to mark his arrival, and then, along with his team, he began to trek into the muck. On the same day, a second man, Joseph Brown, embarked with a separate team at another confluence: the mouth of the St.

Francis River. Both surveyors were veterans—Brown a captain, Robbins a lieutenant—of an army that a few months earlier had been fending off a British invasion. Now, they were official emissaries of the United States government: here not just to scout the landscape but also to lay upon it a perfect rectilinear grid.



Decades earlier, had formed a vision for new territory west of the Appalachian Mountains: It would fuel the creation of an “empire for liberty.” He first used a version of this phrase during the Revolutionary War, in a 1780 letter that urged George Rogers Clark, a surveyor turned soldier, to head north to wrest more land from the British. The frontiersman proved unable to muster sufficient recruits for an expedition, but Jefferson never dropped the idea.

After the Treaty of Paris, which ended the Revolutionary War in 1783, Britain ceded more territory that doubled the size of the U.S. Along with the original 13 colonies, the new country now included territory that stretched all the way to the Mississippi River, to the western edges of what would become Wisconsin, Illinois, Kentucky, Tennesse.