🇺🇸AP US History Unit 7 – Conflict in the Early 20th Century, 1890–1945

Key Events and Timeline

• 1890s saw the rise of American imperialism with the Spanish-American War (1898) resulting in the U.S. acquiring territories in the Caribbean and Pacific
• World War I began in Europe in 1914 after the assassination of Archduke Franz Ferdinand, drawing in multiple nations due to a complex system of alliances
  • The U.S. initially remained neutral but entered the war in 1917 after Germany's unrestricted submarine warfare and the Zimmermann Telegram
• 1920s were marked by economic prosperity, cultural changes (Jazz Age, Harlem Renaissance), and isolationist foreign policy in the U.S.
  • Prohibition, enacted by the 18th Amendment in 1920, banned the production, sale, and transportation of alcohol
• Great Depression began with the stock market crash of 1929, leading to widespread unemployment, poverty, and global economic downturn throughout the 1930s
  • President Franklin D. Roosevelt's New Deal programs aimed to provide relief, recovery, and reform
• World War II erupted in 1939 with Germany's invasion of Poland, and the U.S. entered the war after the attack on Pearl Harbor by Japan in 1941
  • The war ended in 1945 with the surrender of Germany and Japan, following the atomic bombings of Hiroshima and Nagasaki

Major Conflicts and Wars

• Spanish-American War (1898) was a brief conflict between the U.S. and Spain, resulting in the U.S. gaining control over Cuba, Puerto Rico, Guam, and the Philippines
• World War I (1914-1918) was a global conflict involving the Central Powers (Germany, Austria-Hungary, Ottoman Empire) and the Allied Powers (France, Great Britain, Russia, Italy, and later the U.S.)
  • Trench warfare on the Western Front resulted in massive casualties and a stalemate until the arrival of American troops in 1917
  • The war ended with the armistice of November 11, 1918, and the Treaty of Versailles (1919) imposed harsh terms on Germany
• World War II (1939-1945) was another global conflict, with the Axis powers (Germany, Italy, Japan) fighting against the Allies (U.S., Great Britain, Soviet Union, France)
  • The war involved multiple theaters, including Europe, North Africa, and the Pacific
  • The Holocaust, a genocide committed by Nazi Germany, resulted in the deaths of approximately 6 million Jews and other targeted groups
  • The U.S. played a crucial role in the Allied victory, with key events such as D-Day (1944) and the atomic bombings of Hiroshima and Nagasaki (1945)

Political Developments

• Progressive Era (1890s-1920s) saw reforms aimed at addressing social and political issues, such as women's suffrage, child labor, and corruption
  • 19th Amendment (1920) granted women the right to vote nationwide
• Isolationism characterized U.S. foreign policy in the 1920s and 1930s, with the country focusing on domestic issues and avoiding involvement in international conflicts
  • Neutrality Acts of the 1930s aimed to prevent U.S. involvement in foreign wars
• New Deal policies under President Franklin D. Roosevelt expanded the role of the federal government in the economy and social welfare during the Great Depression
  • Programs such as the Civilian Conservation Corps (CCC), Works Progress Administration (WPA), and Social Security aimed to provide relief and stimulate economic recovery
• U.S. foreign policy shifted towards interventionism in the late 1930s as the threat of Nazi Germany and Imperial Japan grew
  • Lend-Lease Act (1941) allowed the U.S. to provide aid to Allied nations before officially entering World War II

Economic Factors

• Industrial growth and technological advancements in the late 19th and early 20th centuries led to the rise of big business and monopolies
  • Antitrust laws, such as the Sherman Antitrust Act (1890) and the Clayton Antitrust Act (1914), aimed to regulate monopolistic practices
• Economic boom of the 1920s, known as the "Roaring Twenties," was characterized by rising consumer spending, stock market speculation, and a growing middle class
  • Overproduction, income inequality, and stock market speculation contributed to the onset of the Great Depression
• Great Depression (1929-1939) was the worst economic downturn in U.S. history, with high unemployment, deflation, and a severe contraction in global trade
  • Dust Bowl, caused by severe drought and poor farming practices, exacerbated the economic hardship in the Great Plains region
• World War II stimulated the U.S. economy, as wartime production and government spending helped to end the Great Depression
  • Rationing and price controls were implemented to manage resources and prevent inflation during the war

Social and Cultural Changes

• Great Migration saw millions of African Americans move from the rural South to urban areas in the North and West, seeking better economic opportunities and escaping racial discrimination
  • Harlem Renaissance, a cultural movement centered in New York City's Harlem neighborhood, celebrated African American art, literature, and music
• Jazz Age of the 1920s was characterized by a spirit of experimentation, freedom, and rebellion against traditional social norms
  • Flappers, young women who embraced short hair, shorter skirts, and a more liberated lifestyle, symbolized the changing gender roles of the era
• Prohibition (1920-1933) led to the rise of organized crime, speakeasies, and a thriving underground alcohol trade
  • 21st Amendment (1933) repealed Prohibition, ending the nationwide ban on alcohol
• Great Depression had a profound impact on American society, with widespread poverty, homelessness, and a sense of despair
  • New Deal programs, such as the Federal Art Project and the Federal Writers' Project, supported artists and writers during the Depression
• World War II led to significant social changes, including increased opportunities for women in the workforce (Rosie the Riveter) and the beginning of the civil rights movement for African Americans
  • Executive Order 9066 (1942) authorized the internment of approximately 120,000 Japanese Americans in camps during the war, a decision later recognized as a grave injustice

Technological Advancements

• Widespread adoption of electricity and the assembly line in the early 20th century revolutionized manufacturing and transformed daily life
  • Mass production techniques, such as those pioneered by Henry Ford in the automobile industry, increased efficiency and made consumer goods more affordable
• Aviation technology advanced rapidly during World War I, with the development of fighter planes and bombers
  • Charles Lindbergh's solo transatlantic flight in 1927 demonstrated the potential of aviation and sparked public interest in air travel
• Radio emerged as a major form of mass communication and entertainment in the 1920s and 1930s
  • Fireside Chats, a series of radio addresses by President Franklin D. Roosevelt, helped to reassure the American public during the Great Depression
• Atomic bomb, developed through the Manhattan Project during World War II, marked a significant advancement in nuclear technology and changed the nature of warfare
  • Radar and sonar technologies, also developed during the war, improved military detection capabilities and had lasting impacts on civilian applications

Key Figures and Their Impacts

• Theodore Roosevelt, president from 1901 to 1909, was known for his "Square Deal" policies, conservation efforts, and the construction of the Panama Canal
• Woodrow Wilson, president during World War I, led the U.S. through the conflict and proposed the League of Nations as part of his "Fourteen Points" plan for postwar peace
  • Wilson's failure to secure U.S. membership in the League of Nations marked a return to isolationism in the interwar period
• Franklin D. Roosevelt, president from 1933 to 1945, implemented the New Deal to combat the Great Depression and led the U.S. through World War II
  • Eleanor Roosevelt, as First Lady, was a prominent advocate for civil rights, women's rights, and social justice
• Harry S. Truman, who became president after Roosevelt's death in 1945, made the decision to use atomic bombs against Japan and oversaw the beginning of the Cold War
• Significant cultural figures, such as Louis Armstrong, Duke Ellington, and Langston Hughes, shaped the artistic landscape of the early 20th century and left lasting legacies in music and literature

Legacy and Long-Term Consequences

• U.S. emergence as a global superpower following World War II, with a strong military, economy, and political influence
  • Cold War, a period of geopolitical tension between the U.S. and the Soviet Union, dominated international relations for decades after the war
• New Deal policies established a precedent for government intervention in the economy and laid the foundation for the modern welfare state
  • Social Security, a key New Deal program, remains a critical component of the U.S. social safety net
• Civil rights movement, which began to gain momentum during World War II, led to landmark legislation in the 1950s and 1960s, such as the Civil Rights Act of 1964 and the Voting Rights Act of 1965
  • Desegregation of the military and the integration of public schools (Brown v. Board of Education, 1954) were significant steps towards racial equality
• Technological advancements of the early 20th century paved the way for future innovations, such as the development of computers, space exploration, and the digital age
• Cultural changes of the era, including the rise of consumerism, the influence of mass media, and the evolution of gender roles, continue to shape American society today