During this time, many people moved to the United States from other countries, such as Ireland, Italy, Germany, Eastern Europe, and China. Many of them worked in large factories and lived in big cities, such as New York City, Chicago, and Boston, often in small, poor, close-together apartments called "tenements" or "slums". They often were used by "political machines", who gave them jobs and money in exchange for votes.
Major politicians were chosen by political machines and were corrupt. The government could do little and leaders of big businesses often had more power than the government. At this time, there were several very big businesses called trusts. People who ran trusts made millions of dollars while paying their workers low wages. Some of these people were John D. Rockefeller, Andrew Carnegie, and J.P. Morgan.
After the Civil War, people continued to move west where new states were formed. People now could get free land in the West due to an 1862 law called the Homestead Act. Most of the land in the West was owned by the government, railroads, or large farmers. The Transcontinental Railroad, finished in 1869, helped get people and goods from the west to the rest of the country. Chicago became the center of trade between West and East because many rail lines met there. There were problems between the white settlers and the native Indians as more people began to move west. Because of this, many more Indians were killed at battles such as Wounded Knee. Almost all the Indians' land was taken away by laws like the Dawes Act.
Many Americans thought the railroads charged farmers so much money that it made them poor. Workers led several strikes against the railroad that were put down by the army. Also, farmers started groups to fight the railroad, such as the Grange. These groups became the Populist Movement, which almost won the presidency under William Jennings Bryan. The Populists wanted reforms such as an income tax and direct election of Senators. The Populist Party died out after 1896. Many of the things the Populists wanted would happen during the Progressive Era.
In the United States, progressivism is the belief that the government should have a larger role in the economy to provide good living standards for people, especially workers. Imperialism was the belief that the U.S. should build a stronger navy and conquer land.
In the late nineteenth and early 20th centuries, the U.S. started being more active in foreign affairs. In 1898, the United States fought a war with Spain called the Spanish–American War. The United States won, and gained Puerto Rico, Guam, Guantanamo and the Philippines. Combined with the purchase of Alaska and the taking-over of Hawaii, the United States had gained all the territory it has today, plus some it would later lose after World War II. Around this time, the U.S. and European nations opened up trade with China. This was because they had beaten China in the Opium Wars and the Boxer Rebellion. The U.S. and Europe were able to trade with China through the Open Door Policy.
In 1901, Theodore Roosevelt became President. He had been a soldier in the Spanish–American War. He called for a foreign policy known as the "Big Stick". This meant having a large navy and exercising control over Latin America. Between 1901 and 1930, the United States sent soldiers into Latin America several times. When Roosevelt was president, work was begun on the Panama Canal, a link between the Pacific and Atlantic Oceans that made travel around the world much faster.
During this time, people started to notice the poor condition of American cities. A group of people called the “muckrakers” wrote books and newspaper articles about subjects like the power of big business, unclean practices in factories, and the condition of poor people. Roosevelt and Congress answered their concerns with laws such as the Pure Food and Drug Act. The Act controlled the way food was made to make sure it was safe. Another response to the muckrakers was something called "trust-busting", where big businesses were broken up into smaller ones. The biggest business broken up this way was the Standard Oil Company in 1911.
In 1912, Woodrow Wilson became President. He was a Progressive, but not quite the same as Roosevelt. He fought the "triple wall of privilege", which was big business, taxes, and fees on goods coming into the United States. During this time, the Sixteenth and Seventeenth Amendments to the U.S. Constitution were passed. They allowed for a federal income tax and direct election of U.S. Senators.
The United States did not want to enter World War I but wanted to sell weapons to both sides. In 1915 a German submarine sank a ship carrying Americans called the "Lusitania". This angered Americans, and Germany stopped attacking passenger ships. In January 1917 Germany started attacking them again, and sent the Zimmerman Telegram to Mexico about invading the U.S. The United States joined the war against Germany, and it ended a year later. Wilson worked to create an international organization called the League of Nations. The main goal of the League was preventing war. However, the United States did not join because isolationists rejected the peace treaty. At the end of World War I, a flu pandemic killed millions of people in the U.S. and Europe. After the war, the United States was one of the richest and most powerful nations in the world.
The 1920s were an era of growth and increased wealth for the United States. Many Americans began buying consumer products, such as Model T Fords and appliances. Advertising became very important to American life. During this time, many black people moved out of the South and into large cities such as New York City, Chicago, St. Louis and Los Angeles. They brought with them jazz music, which is why the 1920s are called the "Jazz Age". The 1920s were also the Prohibition Era after the Eighteenth Amendment passed. During the 1920s, drinking alcohol was illegal, but many Americans drank it anyway. This led to much rum-running and violent crime.
Racism was strong in the 1920s. The Ku Klux Klan was powerful once again, and attacked black people, Catholics, Jews and immigrants. People blamed the war and problems in business on immigrants and labor leaders, whom they said were Bolsheviks (Russian communists). Many people also thought that the United States had lost touch with religion. They handled that by changing religion, and some of them by attacking science.
After World War I, the United States had an isolationist foreign policy. That meant it did not want to enter into another global war. It passed laws and treaties that supposedly would end war forever, and refused to sell weapons to its former allies.
In 1921, Warren G. Harding became President. He believed that the best way to make the economy good was for the government to be friendly to big business by cutting taxes and regulating less. While the economy was doing very well under these policies, America had the largest difference between how much money the rich had and how much money the poor had. Harding's presidency had several problems. The biggest one was Teapot Dome over oil drilling in the Navy Oil Reserve. Harding died in 1923, and Calvin Coolidge became President. Coolidge believed that the government should keep out of business, just like Harding, and continued many of Harding's policies. Coolidge chose not to seek the presidency in 1928 and Herbert Hoover became president.
In 1929, a Great Depression hit the United States. The stock market crashed (lost much of its value). Many banks ran out of money and closed. By 1932, over a quarter of the nation had no jobs, and much of the nation was poor or unemployed. Many people were driven off farms, not only because of the Depression, but also because of a storm known as the "Dust Bowl" and because farmers had not been doing well during the 1920s.