Which factors were the major causes of the red scare and the palmer raids, which followed world war i?

The first reason was the Bolshevik Revolution that happened in 1917 and the second major reason was the strikes organized by the workers in the United States. The government was afraid of the chance that communism would take hold in the United States and that is the reason for the raids and prosecution of the individuals who were thought to be anti-American. 

February 1848 is when it was added. if that's what you were asking