U.S. History Study Guide

1. Colonial America & Independence (1607–1789)

American history begins with European colonization of North America. The thirteen British colonies developed distinct economies: New England colonies relied on trade and shipbuilding; Middle colonies on grain farming; Southern colonies on tobacco, rice, and indigo using enslaved labor. By the 1760s, colonial identity had grown strong enough to resist British taxation without representation.

The American Revolution (1775–1783) produced the Declaration of Independence (1776) — Thomas Jefferson's articulation that "all men are created equal" with unalienable rights to "Life, Liberty, and the pursuit of Happiness." The Constitutional Convention (1787) created the U.S. Constitution — the world's oldest written national constitution still in force — establishing a federal republic with separated powers, checks and balances, and a Bill of Rights (1791).

2. Expansion and Sectionalism (1800–1860)

The young nation expanded dramatically westward. The Louisiana Purchase (1803) doubled U.S. territory. The War of 1812 confirmed American independence from Britain. The Monroe Doctrine (1823) declared the Western Hemisphere off-limits to European colonization. By 1853, the U.S. stretched from the Atlantic to the Pacific.

But expansion intensified conflict over slavery. Each new territory raised the question: would it be free or slave? The Missouri Compromise (1820), Compromise of 1850, and Kansas-Nebraska Act (1854) attempted to resolve this, each time deferring the fundamental contradiction. The Supreme Court's Dred Scott decision (1857) — ruling that enslaved people were property, not citizens — inflamed the North. Abraham Lincoln's election in 1860 triggered Southern secession.

3. Civil War and Reconstruction (1861–1877)

The Civil War (1861–1865) was the deadliest conflict in American history, killing approximately 620,000 soldiers. The Union's victory preserved the nation and ended slavery. Lincoln's Emancipation Proclamation (1863) declared enslaved people in Confederate states free and transformed the war's moral character. The 13th Amendment (1865) abolished slavery permanently.

Reconstruction (1865–1877) attempted to integrate formerly enslaved people as equal citizens. The 14th Amendment granted citizenship and equal protection; the 15th Amendment guaranteed voting rights for Black men. The Freedmen's Bureau provided education and aid. But Reconstruction collapsed with the Compromise of 1877, enabling Jim Crow laws and segregation that suppressed Black civil rights for nearly a century.

4. Industrial Age and Progressive Era (1877–1920)

The late 19th century saw explosive industrial growth: railroads connected the continent, steel mills rose in Pittsburgh, and oil barons (John D. Rockefeller's Standard Oil) accumulated vast fortunes. Immigration peaked — 23 million people arrived 1880–1920, transforming American cities. But industrialization also created poverty, child labor, 16-hour workdays, and dangerous conditions.

The Progressive Era responded: Theodore Roosevelt broke up monopolistic trusts (44 antitrust cases), Upton Sinclair's The Jungle exposed meatpacking horrors (leading to the Pure Food and Drug Act, 1906), and suffragists won women's voting rights with the 19th Amendment (1920). The Federal Reserve (1913) and income tax (16th Amendment, 1913) created modern economic infrastructure.

5. World Wars and the Great Depression (1917–1945)

The U.S. entered World War I in 1917 under President Wilson, tipping the balance against Germany. Wilson's Fourteen Points proposed a just peace and the League of Nations — but the Senate rejected U.S. membership. The 1920s "Roaring Twenties" brought prosperity, jazz, and prohibition before the Great Depression (1929–1939) collapsed the economy: 25% unemployment, bank failures, and the Dust Bowl devastated millions.

FDR's New Deal (1933–1939) created Social Security, the FDIC, the SEC, and public works programs. When Japan attacked Pearl Harbor (December 7, 1941), the U.S. entered World War II. American industrial might — producing half the world's war materiel — proved decisive. President Truman authorized atomic bombs on Hiroshima and Nagasaki (August 1945), ending the Pacific war.

6. Cold War and Civil Rights (1945–1980)

After WWII, the U.S. and Soviet Union entered the Cold War — a global ideological and geopolitical competition between capitalism and communism. The Marshall Plan rebuilt Western Europe; NATO created a military alliance; the Korean War (1950–1953) and Vietnam War (1955–1975) were proxy conflicts. The Cuban Missile Crisis (1962) brought nuclear war closest.

At home, the Civil Rights Movement dismantled legal segregation. Rosa Parks, Martin Luther King Jr., and millions of ordinary citizens — through boycotts, sit-ins, freedom rides, and marches — pressured the federal government to act. The Civil Rights Act (1964) and Voting Rights Act (1965) prohibited racial discrimination in public life. The Great Society programs (Medicare, Medicaid, federal education funding) expanded the social safety net.

7. Modern America (1980–Present)

Reagan's election (1980) marked a conservative turn: tax cuts, deregulation, and Cold War confrontation accelerated Soviet collapse (1991). The 1990s brought economic prosperity and the internet revolution. The September 11, 2001 terrorist attacks launched the War on Terror and reshaped American foreign policy and civil liberties. The 2008 financial crisis required massive government intervention. Barack Obama's election (2008) as the first African American president marked a historic milestone.

The 21st century has seen increasing political polarization, debates over immigration and trade policy, technological disruption, and the COVID-19 pandemic (2020) — the worst public health crisis since 1918. American history remains an ongoing, contested story.

Key U.S. History Terms