Many things can be cited as causes of the Progressive Era. I will look at three of the most important.
- The rise of big business. As businesses got bigger they came to have more and more clout in our system. They corrupted government to get it to help them.
- The increase in immigration. Many immigrants were poor and lived in bad conditions. Many (along with "natives") worked in harsh conditions for low pay. Many of them were also not very "Americanized."
- The increasing size of the middle class. The middle class felt that both the big businesses and the poor and immigrants were ruining America. As the middle class grew in size, it wanted more power so as to be able to deal with these problems. This desire for power and reform caused the Progressive Era.