During the Progressive Era (1900–1920), the country grappled with the problems caused by industrialization and urbanization. Progressivism, an urban, middle‐class reform movement, supported the government taking a greater role in addressing such issues as the control of big business and the welfare of the public. Many of its accomplishments were based on efforts of earlier reform movements. The federal income tax and the direct election of senators, for example, were a part of the Populist program, and Prohibition grew from a pre‐Civil War anti‐alcohol reform tradition. Although the Progressives formed their own political party in 1912, the movement had broad support among both Democrats and Republicans. Presidents Theodore Roosevelt and William Howard Taft (Republicans) and Woodrow Wilson (Democrat) all claimed the Progressive mantle.
The need for reform was highlighted by a group of journalists and writers known as the muckrakers, who made Americans aware of the serious failings in society and built public support for change. Exposés such as Lincoln Steffens' The Shame of the Cities (1904), an attack on municipal corruption, and Ida Tarbell's History of the Standard Oil Company (1904), which chronicled John D. Rockefeller's ruthless business practices, often first appeared in the new mass circulation magazines, such as McClure's and Cosmopolitan, and were later published as books. The muckrakers' impact could be powerful, as in the case of Upton Sinclair's The Jungle (1906), a book whose vivid descriptions of working and sanitary conditions in Chicago's meatpacking plants led directly to federal laws regulating the industry.