APUSH Ch. 21 Terms

Theodore Roosevelt

26th President of the United States (1901–1909), known for his aggressive foreign policy, trust-busting, conservation efforts, and expanding American power on the world stage.

Russo-Japanese War

A 1904–1905 conflict between Russia and Japan over influence in Manchuria and Korea; Japan won decisively, and Roosevelt mediated the peace settlement, earning him the Nobel Peace Prize.

Great White Fleet

The nickname for the 16 U.S. battleships Roosevelt sent on a world tour (1907–1909) to demonstrate American naval power and signal U.S. emergence as a global military force.

Roosevelt Corollary

A 1904 addition to the Monroe Doctrine asserting the U.S. right to intervene in Latin American nations unable to maintain order or pay foreign debts, effectively making the U.S. the "police" of the Western Hemisphere.

John Hay

U.S. Secretary of State under McKinley and Roosevelt, best known for the Open Door Notes regarding China and for negotiating the framework that led to the Panama Canal treaty.

Panama Canal

A 47-mile waterway built by the U.S. through Panama (completed 1914) connecting the Atlantic and Pacific Oceans, a major engineering and strategic achievement of the Roosevelt era.

Philippe Bunau-Varilla

A French engineer and lobbyist who helped persuade the U.S. to build the canal through Panama rather than Nicaragua, and later negotiated the Hay–Bunau-Varilla Treaty giving the U.S. control of the Canal Zone.

Dollar Diplomacy

The foreign policy of President Taft that used American economic investment and financial leverage, rather than military force, to extend U.S. influence, particularly in Latin America and Asia.

Francisco Madero

A Mexican reformer and politician who led the revolution that overthrew dictator Porfirio Díaz in 1911, became president of Mexico, but was subsequently overthrown and assassinated in 1913 by General Huerta.

General Huerta

Victoriano Huerta, a Mexican military general who seized power in 1913 after orchestrating the assassination of Madero; his government was refused recognition by President Wilson, leading to U.S. military intervention.

Pancho Villa

A Mexican revolutionary leader who raided Columbus, New Mexico in 1916, killing American civilians and soldiers, prompting the U.S. to send a punitive expedition into Mexico to capture him.

John J. Pershing

U.S. Army general who led the failed Punitive Expedition into Mexico to capture Pancho Villa and later commanded the American Expeditionary Forces (AEF) in Europe during World War I.

MAIN Causes of WW1

Militarism (arms race among European powers), Alliance systems (Triple Entente vs. Triple Alliance), Imperialism (competition for colonies), and Nationalism (ethnic and political tensions, particularly in the Balkans).

Archduke Franz Ferdinand

Heir to the Austro-Hungarian throne whose assassination in Sarajevo on June 28, 1914 by Gavrilo Princip, a Bosnian-Serb nationalist, served as the immediate trigger for World War I.

Lusitania

A British ocean liner sunk by a German U-boat on May 7, 1915, killing 1,198 people including 128 Americans; the incident outraged U.S. public opinion and increased pressure to enter the war.

Sussex

A French passenger ferry torpedoed by Germany in 1916; the resulting Sussex Pledge was Germany's promise to warn ships before attacking, temporarily easing tensions with the U.S.

League of Nations

An international peacekeeping organization proposed by Woodrow Wilson in his Fourteen Points and established by the Treaty of Versailles, intended to resolve future conflicts diplomatically; the U.S. Senate refused to join.

Self-Determination

The principle, championed by Wilson, that peoples and nations have the right to choose their own government and political status, a key concept at the Paris Peace Conference that reshaped the map of Europe.

Unrestricted Submarine Warfare

Germany's policy of using U-boats to sink any ship, including neutral and civilian vessels, found in war zones without warning; its resumption in 1917 was a key factor in drawing the U.S. into WWI.

Zimmermann Telegram

A secret 1917 message from German Foreign Secretary Arthur Zimmermann to Mexico proposing a military alliance against the U.S., promising Mexico the return of Texas, New Mexico, and Arizona; its interception and publication helped push the U.S. toward war.

Russian Revolution

The 1917 overthrow of Tsar Nicholas II followed by the Bolshevik seizure of power under Lenin, leading Russia to withdraw from WWI and establishing the world's first communist state.

Convoys

A naval strategy adopted by the Allies in 1917 where merchant ships traveled in groups escorted by warships, dramatically reducing losses to German U-boats.

Selective Service Act

A 1917 law establishing the military draft in the United States, requiring men between the ages of 21 and 30 (later expanded) to register for potential military service in WWI.

Armistice

The agreement signed on November 11, 1918 at 11 a.m. that ended the fighting on the Western Front, effectively concluding World War I.

Trench Warfare

The dominant style of combat on the Western Front in WWI, where opposing armies faced each other from networks of fortified ditches, resulting in massive casualties and little territorial gain.

Liberty Bonds

Government-issued war bonds sold to American citizens to help finance U.S. involvement in WWI, promoted heavily through patriotic campaigns and celebrity endorsements.

Council of National Defense

A federal advisory body created in 1916 to coordinate wartime industrial resources, transportation, and economic production to support the war effort.

War Boards

Government agencies created during WWI to manage and coordinate specific sectors of the economy, such as the War Industries Board, Food Administration, and Fuel Administration.

Bernard Baruch

A financier who chaired the War Industries Board during WWI, overseeing the mobilization and allocation of industrial production for the war effort with broad governmental authority.

National War Labor Board

A federal agency established in 1918 to mediate labor disputes during WWI, helping to prevent strikes that could disrupt war production while securing some protections for workers.

Ludlow Massacre

The 1914 attack by Colorado National Guard and company guards on a tent colony of striking miners and their families in Ludlow, Colorado, killing over 20 people including women and children.

Women in Industry Board

A wartime agency that studied and set standards for the working conditions of women employed in war industries, recognizing the massive influx of women into the industrial workforce during WWI.

Great Migration

The large-scale movement of African Americans from the rural South to Northern and Midwestern cities beginning around 1910–1920, driven by economic opportunity in war industries and escape from Jim Crow laws.

Women's Peace Party

An organization founded in 1915 by Jane Addams and others advocating for a negotiated end to WWI and opposing U.S. entry into the conflict, reflecting a significant strand of female-led anti-war activism.

Billy Sunday

A prominent evangelical Christian revivalist preacher who used his platform to enthusiastically support U.S. involvement in WWI, framing the war as a moral and religious crusade.

CPI (Committee on Public Information)

A government propaganda agency created in 1917 and led by George Creel to mobilize public opinion in favor of the war through posters, pamphlets, films, and public speakers known as "Four-Minute Men."

Espionage Act

A 1917 law making it a federal crime to interfere with military recruitment, obstruct the draft, or aid the enemy; used to prosecute anti-war activists and suppress dissent.

Sedition Act

A 1918 amendment to the Espionage Act that made it illegal to speak, write, or publish anything disloyal, profane, or abusive about the U.S. government, Constitution, or military, severely limiting free speech during wartime.

Eugene Debs

A prominent socialist leader and labor organizer who was convicted and imprisoned under the Espionage Act for giving an anti-war speech in 1918; he ran for president from prison in 1920.

American Protective League

A private, government-sanctioned organization of volunteers who conducted surveillance on fellow citizens during WWI, reporting suspected disloyalty, draft evasion, and sedition to federal authorities.

100% Americanism

A nativist ideology promoted during and after WWI demanding complete loyalty to the United States and its culture, often used to justify hostility toward immigrants, radicals, and anyone deemed insufficiently patriotic.

V.I. Lenin

Vladimir Ilyich Lenin, the Bolshevik revolutionary leader who led the October Revolution in 1917 and became the head of the Soviet state, withdrawing Russia from WWI and establishing communist rule.

Paris Peace Conference

The 1919 international meeting at which the Allied powers negotiated the terms of peace following WWI, resulting in the Treaty of Versailles and other treaties that reshaped the world map.

Big Four

The dominant leaders at the Paris Peace Conference: Woodrow Wilson (U.S.), David Lloyd George (Britain), Georges Clemenceau (France), and Vittorio Orlando (Italy), who made the major decisions on peace terms.

Treaty of Versailles

The 1919 peace treaty ending WWI that imposed heavy reparations and territorial losses on Germany, assigned Germany sole "war guilt," created the League of Nations, and laid groundwork for future instability in Europe.

Henry Cabot Lodge

Republican Senator and Senate Majority Leader who led opposition to the Treaty of Versailles in the U.S. Senate, arguing it surrendered too much American sovereignty to the League of Nations.

Reservationists

Senators, led by Lodge, who were willing to ratify the Treaty of Versailles only with significant amendments or reservations limiting U.S. obligations under the League of Nations covenant.

Economic Reconversion

The post-WWI transition of the American economy from wartime military production back to civilian consumer goods production, a process marked by inflation, labor unrest, and economic disruption.

Boston Police Strike

The 1919 strike by Boston police officers protesting low wages and poor conditions; Governor Calvin Coolidge's firm response in breaking the strike brought him national attention and helped propel him toward the vice presidency.

Chicago Race Riots

A violent conflict in the summer of 1919 lasting 13 days, triggered by racial tensions and the killing of a Black teenager at a segregated beach, resulting in dozens of deaths and hundreds injured.

Red Summer

The summer and fall of 1919, named by writer James Weldon Johnson, characterized by widespread race riots and anti-Black violence across the United States as racial tensions exploded in dozens of cities.

UNIA (Universal Negro Improvement Association)

An organization founded by Marcus Garvey in 1914 dedicated to Black pride, self-reliance, Pan-African unity, and the goal of returning African Americans to Africa.

Marcus Garvey

A Jamaican-born Black nationalist leader who founded the UNIA and promoted Pan-Africanism, Black pride, and economic self-sufficiency, becoming one of the most influential Black leaders of the early 20th century.

Red Scare

The widespread fear of communist, socialist, and anarchist subversion that gripped the United States after WWI and the Russian Revolution, leading to raids, deportations, and suppression of political radicals.

A. Mitchell Palmer

U.S. Attorney General who led the Palmer Raids of 1919–1920, a series of aggressive government actions targeting suspected radicals, communists, and anarchists, deporting hundreds of immigrants.

Sacco and Vanzetti

Two Italian-born anarchists convicted of murder and robbery in Massachusetts in 1921 in a controversial trial widely seen as motivated by anti-immigrant and anti-radical prejudice; they were executed in 1927.

Warren G. Harding

The 29th President (1921–1923) who won the 1920 election on a platform of "normalcy," promising a return to pre-war life; his administration was marked by scandal, most notably the Teapot Dome affair.

Normalcy

Harding's campaign slogan referring to a return to the pre-WWI way of life — away from Progressive reform, wartime government expansion, and international entanglements — reflecting American desire to retreat from global engagement.