Which group committed violence against african americans in the late 1800s and early 1900s?

The group that committed violence against African Americans in the late 1800s and early 1900s was the Klu Klux Klan.

The first incarnation of the Klan was founded at the end of 1865 by veterans after the Civil War, who wanted to resist reconstruction. The organization quickly adopted violent methods to achieve its ends. However, there was a reaction that soon led the organization to decline, as the southern elites saw the Klan as a pretext for federal troops to be active in the southern states. The KKK was formally dissolved by Republican President Ulysses Grant, through the Civil Rights Act of 1871 (known as the Ku Klux Klan Act).

In 1915 a new association with the same name was founded, inspired by the power of the mass media. The film The Birth of a Nation and the anti-Semitism shown in the journalistic chronicles of the trial and lynching of Leo Frank contributed to this inspiration. The second KKK was a more formal organization, with registered members and with a state and national structure. It reached 4 to 5 million members, its popularity began to fall in the Great Depression of 1929 and during the Second World War, as some prominent members of the Klan staged scandals to support Nazi Germany.

the answer is a, salt plain