Who used violence against innocent civilians to obtain concessions by government or to gain media attention?

They are the terrorists. They used unlawful violence and threat to create intense fear to control the situation to their benefit and attain their political goals. They may be motivated by some political organizations, by nationalistic and religious groups or just by their greed.

If i’m not mistaken your answer should be the freemen’s bureau started them. i really hope i could ! good luck