1900-1929: Library of Congress
The early 20th century was an era of business expansion and progressive reform in the United States. The progressives, as they called themselves, worked to make American society a better and safer place in which to live. They tried to make big business more responsible through regulations of various kinds. They worked to clean up corrupt city governments, to improve working conditions in factories, and to better living conditions for those who lived in slum areas, a large number of whom were recent immigrants from Southern and Eastern Europe. Many progressives were also concerned with the environment and conservation of resources.
See the First-wave Feminism, from Wikipedia:
First-wave feminism was a period of feminist activity and thought that occurred during the 19th and early 20th century throughout the Western world. It focused on legal issues, primarily on securing women's right to vote. The term is often used synonymously with the kind of feminism espoused by the liberal women's rights movement with roots in the first wave, with organizations such as the International Alliance of Women and its affiliates. This feminist movement still focuses on equality from a mainly legal perspective.
See the Nadir of American Race Relations, from Wikipedia:
The nadir of American race relations was the period in African-American history and the history of the United States from the end of Reconstruction in 1877 through the early 20th century, when racism in the country, and particularly anti-black racism, was more open and pronounced than it had ever been during any other period in the nation's history. During this period, African Americans lost access to many of the civil rights which they had gained during Reconstruction. Anti-Black violence, lynchings, segregation, legalized racial discrimination, and expressions of white supremacy all increased. Asian Americans and Hispanic Americans were also not spared from such sentiments.
See the Progressive Era, from Wikipedia:
The Progressive Era (1901–1929) was a period in the United States during the early 20th century of widespread social activism and political reform across the country. Progressives sought to address the problems caused by rapid industrialization, urbanization, immigration, and political corruption as well as the enormous concentration of industrial ownership in monopolies. Progressive reformers were alarmed by the spread of slums, poverty, and the exploitation of labor. Multiple overlapping progressive movements fought perceived social, political, and economic ills by advancing democracy, scientific methods, and professionalism; regulating business; protecting the natural environment; and improving working and living conditions of the urban poor.
See the Lochner Era, from Wikipedia:
The Lochner era was a period in American legal history from 1897 to 1937 in which the Supreme Court of the United States is said to have made it a common practice "to strike down economic regulations adopted by a State based on the Court's own notions of the most appropriate means for the State to implement its considered policies". The court did this by using its interpretation of substantive due process to strike down laws held to be infringing on economic liberty or private contract rights. The era takes its name from a 1905 case, Lochner v. New York. The beginning of the era is usually marked earlier, with the Court's decision in Allgeyer v. Louisiana (1897), and its end marked forty years later in the case of West Coast Hotel Co. v. Parrish (1937), which overturned an earlier Lochner-era decision.
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In his confirmation hearings to become Chief Justice, John Roberts said: "You go to a case like the Lochner case, you can read that opinion today and it's quite clear that they're not interpreting the law, they're making the law." He added that the Lochner court substituted its own judgment for the legislature's findings.
See Great Migration (African American), from Wikipedia:
The Great Migration, sometimes known as the Great Northward Migration or the Black Migration, was the movement of six million African Americans out of the rural Southern United States to the urban Northeast, Midwest, and West between 1910 and 1970. It was substantially caused by poor economic and social conditions due to prevalent racial segregation and discrimination in the Southern states where Jim Crow laws were upheld. In particular, continued lynchings motivated a portion of the migrants, as African Americans searched for social reprieve. The historic change brought by the migration was amplified because the migrants, for the most part, moved to the then-largest cities in the United States (New York City, Chicago, Detroit, Los Angeles, San Francisco, Philadelphia, Cleveland, and Washington, D.C.) at a time when those cities had a central cultural, social, political, and economic influence over the United States; there, African Americans established culturally influential communities of their own. According to Isabel Wilkerson, despite the loss of leaving their homes in the South, and the barriers faced by the migrants in their new homes, the migration was an act of individual and collective agency, which changed the course of American history, a "declaration of independence" written by their actions.
See World War I, from Wikipedia:
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a global conflict between two coalitions: the Allies (or Entente) and the Central Powers. Fighting took place mainly in Europe and the Middle East, as well as in parts of Africa and the Asia-Pacific, and in Europe was characterised by trench warfare and the use of artillery, machine guns, and chemical weapons (gas). World War I was one of the deadliest conflicts in history, resulting in an estimated 9 million military dead and 23 million wounded, plus up to 8 million civilian deaths from causes including genocide. The movement of large numbers of people was a major factor in the Spanish flu pandemic, which killed millions.
See the First Red Scare, from Wikipedia:
The first Red Scare was a period during the early 20th-century history of the United States marked by a widespread fear of far-left movements, including Bolshevism and anarchism, due to real and imagined events; real events included the Russian 1917 October Revolution, German Revolution of 1918–1919, and anarchist bombings in the U.S. At its height in 1919–1920, concerns over the effects of radical political agitation in American society and the alleged spread of socialism, communism, and anarchism in the American labor movement fueled a general sense of concern.
See Prohibition in the United States, from Wikipedia:
The Prohibition era was the period from 1920 to 1933 when the United States prohibited the production, importation, transportation, and sale of alcoholic beverages. The alcohol industry was curtailed by a succession of state legislatures, and Prohibition was formally introduced nationwide under the Eighteenth Amendment to the United States Constitution, ratified on January 16, 1919. Prohibition ended with the ratification of the Twenty-first Amendment, which repealed the Eighteenth Amendment on December 5, 1933.
See The Roaring Twenties, from Wikipedia:
The Roaring Twenties, sometimes stylized as Roaring '20s, refers to the 1920s decade in music and fashion, as it happened in Western society and Western culture. It was a period of economic prosperity with a distinctive cultural edge in the United States and Europe, particularly in major cities such as Berlin, Buenos Aires, Chicago, London, Los Angeles, Mexico City, New York City, Paris, and Sydney. In France, the decade was known as the années folles ('crazy years'), emphasizing the era's social, artistic and cultural dynamism. Jazz blossomed, the flapper redefined the modern look for British and American women, and Art Deco peaked.
See The Jazz Age, from Wikipedia:
The Jazz Age was a period in the 1920s and 1930s in which jazz music and dance styles gained worldwide popularity. The Jazz Age's cultural repercussions were primarily felt in the United States, the birthplace of jazz. Originating in New Orleans as mainly sourced from the culture of African Americans, jazz played a significant part in wider cultural changes in this period, and its influence on popular culture continued long afterwards.
The Jazz Age is often referred to in conjunction with the Roaring Twenties, and overlapped in significant cross-cultural ways with the Prohibition Era. The movement was largely affected by the introduction of radios nationwide. During this time, the Jazz Age was intertwined with the developing youth culture. The movement would also help in introducing jazz culture to Europe.