In 1789, Saint-Domingue (today's Haiti) was the most profitable colony in the entire world. Today Haiti is the poorest country in the Western Hemisphere.17
Napoleon's armies suffered more casualties fighting in Saint-Domingue than at his famous defeat at Battle of Waterloo.18
In 1805 (when Lewis & Clark spent the winter there) more people lived in the sprawling villages of the Mandan (near modern-day Bismarck, North Dakota) than in either St. Louis or Washington, D.C.19
Lewis and Clark were fascinated by the prairie dog, a species never encountered in the eastern United States. They captured one and sent it back, live, to Thomas Jefferson in the White House.20
Thomas Jefferson believed the Louisiana Purchase was unconstitutional.21
The Louisiana Purchase instantly doubled the geographical size of the United States.