Slaves in the French sugar colony of Saint-Domingue (today's Haiti) launch a massive uprising against the island's planters and French colonial rule.
The French revolutionary assembly in Paris abolishes slavery in all French colonies, hoping to gain the loyalty of ex-slave leaders such as Toussaint Louverture in order to resist invasion attempts from Spain and England against Saint-Domingue.
The United States and Spain sign a treaty guaranteeing Americans the "right of deposit" in the Spanish port of New Orleans. The treaty means that Americans in the vast Mississippi Valley now have the right to navigate the entire Mississippi River and to store goods in New Orleans in order to facilitate export.
In the secret Treaty of San Ildefonso, French Emperor Napoleon Bonaparte acquires the Louisiana Territory from Spain. Napoleon hopes to use the vast territory on the North American mainland to supply a renewed French sugar empire in the Caribbean with food, cotton, lumber, and other staples.
Toussaint Louverture's ex-slave army conquers Spanish Santo Domingo (today's Dominican Republic), liberating all slaves on the island of Hispaniola and uniting the island under Toussaint's rule.
Toussaint Louverture proclaims a new constitution for Saint-Domingue, establishing himself as a powerful Governor-General for life even while declaring his loyalty to France and Napoleon.
For the first time, American commerce through the port of New Orleans—chiefly agricultural produce, furs, and lumber—exceeds $1 million a year.
Napoleon sends a huge army of 40,000 men, led by his brother-in-law Charles Leclerc, to reconquer Saint-Domingue and depose Toussaint Louverture.
Napoleon attempts to restore slavery in Saint-Domingue, provoking fierce resistance from the island's ex-slave population.
Toussaint Louverture is deported from Saint-Domingue to France, where he will be confined to the dungeon of castle Fort-de-Joux in Doubs until his death from pneumonia in April 1803.
General Leclerc, commander of Napoleon's expedition to Saint-Domingue, dies of yellow fever. The French army, decimated by fierce resistance from ex-slaves as well as by fearsome tropical diseases, has lost the war for Saint-Domingue.
Congress appropriates $2500 to fund an expedition of discovery through the uncharted West (including a good chunk of the Louisiana Territory, which remains French territory) to the Pacific.
Napoleon offers to sell the United States not only the port of New Orleans, but the entire Louisiana Territory.
American envoys Robert Livingston and James Monroe conclude negotiations to purchase the entire Louisiana Territory for $15 million, doubling the size of the United States for a cost of about 3 cents an acre. Livingston and Monroe have been authorized by President Jefferson only to obtain the city of New Orleans.
Meriwether Lewis, President Jefferson's choice to lead the Corps of Discovery to the Pacific, writes to Army officer William Clark, asking him to be the co-leader of the expedition. Clark accepts in July.
President Thomas Jefferson addresses his detailed instructions for the Pacific expedition to its leader, Meriwether Lewis. Jefferson's ambitious agenda includes navigation and mapmaking, diplomacy with Indians, and extensive scientific observation.
Lewis and Clark make their first peaceful encounter with Indians, near the site of modern-day Council Bluffs, Iowa.
President Thomas Jefferson announces the Louisiana Purchase to the American people.
Meriwether Lewis leaves Pittsburgh with 11 men, heading west with the nucleus of what will become the Corps of Discovery.
Congress ratifies the treaty authorizing the Louisiana Purchase.
Jean-Jacques Dessalines, the most powerful black leader remaining in Saint-Domingue after Toussaint Louverture's death, declares independence for the new nation of Haiti.
The city of St. Louis hosts an official ceremony commemorating the transfer of Louisiana from France to the United States. Lewis and Clark are in attendance.
The Lewis & Clark expedition departs from its winter encampment at Fort Dubois, Illinois, paddling up the Missouri River toward the unknown.
The Lewis & Clark expedition suffers its first (and only) casualty, as Sergeant Charles Floyd dies of a burst appendix.
Lewis and Clark arrive at the villages of the Mandan (north of the site of modern-day Bismarck, North Dakota), which are home to more than 4,500 friendly Indians. The Corps of Discovery builds its winter encampment there, calling it Fort Mandan.
The Lewis & Clark expedition departs Fort Mandan, paddling west up the Missouri River.
Lewis and Clark arrive at the Great Falls of the Missouri, near present-day Great Falls, Montana. Their arrival at the spectacular landmark, which has been described to them by Indians, confirms that they are going the right way but also presents them with a major obstacle. Portaging around the falls will take nearly a month.
Meriwether Lewis reaches the Continental Divide, high in the Rocky Mountains.
A starving Corps of Discovery struggles through a brutal overland journey through the Bitterroot Mountains of Idaho. This is the most arduous part of their voyage.
Using new canoes built with the guidance of friendly Nez Perce Indians, Lewis and Clark swiftly float downstream from the Snake River into the Columbia River.
Lewis and Clark reach the Pacific Ocean, at the mouth of the Columbia River near present-day Astoria, Oregon.
The Corps of Discovery builds Fort Clatsop, its winter encampment at the mouth of the Columbia River. Over the course of four months spent at the fort, only twelve days do not bring rain.
Lewis and Clark abandon Fort Clatsop, beginning their long journey home.
In the Lewis & Clark expedition's sole violent encounter with Indians, Meriwether Lewis's traveling party shoots and kills two aggressive Blackfeet warriors.
The Lewis & Clark expedition reaches the Mandan villages, site of their winter encampment two years earlier.
The Corps of Discovery makes its triumphant return to St. Louis.