The Louisiana Purchase nearly doubled America’s size in 1803

The 1783 peace treaty with Britain formally ended the Revolutionary War and nearly doubled the size of the United States.

Madison urged Jefferson to accept the Louisiana Purchase despite constitutional concerns

As secretary of state, James Madison helped negotiate the 1803 Louisiana Purchase and persuaded Thomas Jefferson to proceed, arguing that the strategic and economic stakes outweighed the unresolved constitutional questions.

Jefferson feared European control in the West of North America

Jefferson pushed for the Louisiana Purchase to prevent France or Spain from dominating the western frontier, securing control of the Mississippi River and vast lands that he felt were essential to America’s strategic and economic future.

Jefferson omitted a plan to go beyond the Louisiana Territory in his funding request

In January of 1803, the president sought $2,500 to fund the expedition (though it likely cost closer to $50,000). The ostensible rationale for the journey was to explore the newly purchased territory, but Jefferson did not mention he wanted Lewis and Clark to go beyond the newly acquired territory for several reasons.

As president, Thomas Jefferson expanded federal power despite opposing centralized authority

Although Jefferson argued for limited national power, his presidency expanded federal authority through actions such as the Louisiana Purchase, territorial governance, and federal enforcement—reflecting a pragmatic departure from his earlier strict interpretation of the Constitution.

Jefferson sent Lewis and Clark to map, trade, and secure the West

Beyond seeking a water route to the Pacific, Jefferson tasked the Corps of Discovery with mapping the new Louisiana Territory, cataloging its resources, and establishing trade with Native nations.

How the US took half of Mexico

In just two years, the United States redrew the map of North America. Sparked by border disputes in Texas and fueled by President James Polk’s drive for expansion, the Mexican–American War (1846–1848) reshaped both nations.

The Missouri Compromise temporarily eased tensions over slavery's expansion

Passed in 1820, the Missouri Compromise admitted Missouri as a slave state and Maine as a free state—maintaining the fragile balance between proslavery and antislavery states in Congress. It also banned slavery north of latitude 36°30′.

The Treaty of Guadalupe Hidalgo forced Mexico to surrender over half its territory

Signed in 1848, the Treaty of Guadalupe Hidalgo ended the war but came at a steep cost for Mexico—ceding 55% of its territory, including California and the Southwest, in exchange for $15 million and vague promises to protect Mexican residents.

Jefferson’s Lewis and Clark expedition joined the centuries-long hunt for Northwest Passage

For centuries, leaders pursued a direct seafaring trade route from Europe to Asia. Jefferson joined this quest by sending Lewis and Clark west, though they confirmed no such practical interior route existed across the continent.

The Lewis and Clark expedition purchased more than 260 separate items to supply their journey.

US westward expansion—and the status of slavery in the new territories—was a major cause of the American Civil War

The addition of new western lands forced the nation to confront whether slavery would spread beyond the South. Each debate over the admission of a new state sharpened the divide between free and slaveholding regions.

Americans touring the Louvre were inspired to create their own grand museums

The one-time royal residence was first transformed into a public museum in 1793 amid the French Revolution. Americans visiting in the early 1800s were both turned off by the aristocratic grandeur and compelled by the open access to the public. James Fenimore Cooper, the author of "The Last of the Mohicans," apparently came and measured the length of galleries.

Explore Lewis and Clark's 8,000-mile journey in Google Earth.

At age 22, Washington inadvertently started the French and Indian War.

The Lewis and Clark expedition lasted over two years

The Corps of Discovery departed St. Louis in May 1804 and returned in September 1806, covering more than 8,000 miles by boat, horseback, and on foot. See a timeline of the journey’s key events.

The US finished what the French had started with Panama's canal

For about two decades, Suez Canal-builder and Frenchman Ferdinand de Lesseps led the project, but financial troubles forced it into the hands of the US, who completed it in 1914. This timeline, made to accompany the definitive PBS American Experience documentary about the canal, highlights major moments in its construction.

John Marshall gained national prominence during the XYZ Affair

In 1797, President John Adams sent Marshall to France amid seizures of American ships. French intermediaries demanded loans and bribes before talks, and Marshall refused. Publication of the dispatches fueled the Quasi-War and elevated his reputation in the United States.

Meriwether Lewis grew up in the same neighborhood as Jefferson

Hailing from Jefferson’s Albemarle County neighborhood in Virginia, Lewis was a trusted aide and former Army officer. After leading the Corps of Discovery, he became Louisiana Territory governor in 1806, dying three years later under mysterious circumstances.

William Clark negotiated one-tenth of all ratified treaties between Native Americans and the US.

National parks, explained

Roughly 83 million acres of the United States are set aside as federal National Parks land, an area large as Germany. From the original Yellowstone Park to small monuments and memorials, learn the essentials on this portion of America dedicated to public enjoyment and recreation with our quick explainer video.

The Declaration of Independence was not only a statement of principles but also an appeal for military allies that the struggling colonists needed to survive.

Manifest destiny fueled US aggression against Mexico

The belief that the United States had a divine right to expand westward—known as manifest destiny—justified President Polk’s push for territorial conquest. It shaped public support for the Mexican-American War and framed the invasion as national destiny.

The trans-Atlantic slave trade brought over 10 million enslaved people to the Americas.

The Compromise of 1850 tried to settle disputes over land gained from Mexico

Territory acquired in the Mexican-American War reignited fierce debates over slavery’s expansion. The Compromise of 1850 aimed to ease tensions by admitting California as a free state and letting other territories decide the issue—but the compromise ultimately failed and helped pave the way to the Civil War.

Some historians claim that Mexico's victory at Puebla may have prevented France from arming the Confederacy

According to some experts, Napoleon III planned to ship weapons from Mexico to Confederate forces to break the Union naval blockade. The delay caused by the Battle of Puebla meant French resources didn't reach the Texas border until after the Union Army's decisive victory at Vicksburg.

American annexation of Texas eventually sparked war with Mexico

After Texas won independence from Mexico in 1836, the US annexed it in 1845—despite Mexico’s refusal to recognize Texas as separate. That annexation, combined with a heated border dispute, triggered the Mexican-American War the following year.

The Compromise of 1790 broke a deadlock over debt and the national capital

In 1790, Alexander Hamilton, James Madison, and Thomas Jefferson reached an agreement that allowed Congress to assume the states' war debts and to approve a permanent national capital on the Potomac River.

The National Archives protects billions of historical documents, including the Declaration of Independence and the US Constitution.

This "60 Minutes" segment takes viewers behind the scenes at the National Archives, showcasing how experts use conservation science, security, and technology to preserve cornerstone records—such as the original Declaration of Independence—for future generations.

The US has carried debt since 1791

After the Revolutionary War, the US owed $75M to nations like France. Debt builds when spending exceeds revenue, funding programs, wars, and economic recovery efforts. Most debt is domestic, like Social Security bonds, with foreign nations also holding a share.

Voting rights expanded from 6% of Americans in 1789 to nearly all adult citizens today.

Travel the 363-mile Erie Canal, the waterway that cut freight costs by 90% and opened the American frontier.

Near the end of the 1700s, the United States was forced to pay Barbary pirates an annual tribute equal to 16% of its entire budget.

In the midst of the Civil War, Lincoln rapidly expanded presidential power

Abraham Lincoln suspended habeas corpus, expanded the army without congressional approval, and issued the Emancipation Proclamation—despite likely lacking authority to unilaterally alter national slave law. His actions set precedents for expanded presidential power in wartime.

Foreign policy and war defined Madison's presidency

During James Madison's presidency, disputes with Britain and France over trade, maritime rights, and impressment dominated foreign policy, culminating in the War of 1812 and shaping how the United States engaged with major European powers.

The Lewis and Clark Expedition brought along an estimated 120 gallons of whiskey and still ran out of alcohol halfway through the journey.

European powers largely dismissed Monroe's declaration initially

The reaction in Europe ranged from quiet acceptance in Britain to outrage from Austria's Prince Metternich, who privately called it a "new act of revolt." At home, US newspapers reported a "warm and universal burst of applause," and Congress responded positively to the address.

The power and influence of the American presidency have expanded significantly over time—far beyond what the founders envisioned.

President Polk deliberately provoked war with Mexico

After Mexico refused to sell California and New Mexico, President James K. Polk ordered US troops into disputed territory between the Nueces River and the Rio Grande—knowing it would likely spark a conflict. When fighting broke out, he used it to justify declaring war.

The Civil War permanently strengthened federal power

The Civil War expanded federal power through emancipation, national military mobilization, and postwar civil rights laws, permanently strengthening the national government and shifting the balance of authority away from the states.

The highest inflation ever recorded in US history was estimated at 30% in 1778, just after the Revolutionary War.

Clark’s maps provided the first detailed record of the American West

Covering over 8,000 miles, William Clark’s maps charted rivers, mountains, and tribal territories with remarkable accuracy. Equipped with sextants, compasses, telescopes, and more, Clark became an expert at surveying—requiring extensive celestial and topographical observations each day.

The Panama Canal boosted the US as a world power in trade, engineering, and finance

The effort proved the US could achieve grand engineering projects while granting it influence over (and benefitting economically from) a major interoceanic channel and its host country, Panama.

The Erie Canal fueled a surge in westward settlement

By providing cheap, reliable transport to the interior, the canal made western lands more accessible. Farmers, traders, and immigrants moved into the Great Lakes region, accelerating population growth.

Lewis and Clark’s journey became a blueprint for future exploration

Combining science, diplomacy, and logistics, the Corps of Discovery created a model for later expeditions—from charting the Arctic to NASA’s space missions.

The first test of America's war powers came just a decade after the Constitution was ratified

During the undeclared Quasi-War with France in 1800, the Supreme Court ruled in Bas v. Tingy that Congress had authorized a valid "imperfect war" through statutes alone, without a formal declaration, establishing that there is a legal spectrum between peace and declared war.

The Monroe Doctrine helped lead to the American occupation of territory abroad

This podcast explores how the policy motivated a century of US military intervention throughout Latin America, the Caribbean, and the Pacific—covering the annexation of Hawaii, the Spanish-American War, and occupations of Cuba, Haiti, and Panama.

The US exported $426.3B in goods to Canada and imported $453.6B in goods from Canada in 2025.

The Continental Army invaded Canada in an attempt to seize Montreal and Quebec City in 1775.

See Pierre L'Enfant's original plan and vision for DC and the National Mall