Answer:
The Ku Klux Klan.
Step-by-step explanation:
The Ku Klux Klan was an organization created in 1865 in the South of the U.S. They were against equal rights for all Americans, immigrants, certain religions, and political parties. The Ku Klux Klan believed in white supremacy and a hierarchical organization of the society based on race, which was what the Republicans were trying to change. To achieve their goals, they used violence and terrorism.
After World War I, there was a revival of this organization. They strongly opposed immigrants since they claimed that they took jobs that Americans could do in a context where industrialization was changing the order of the world.