 In 1954, the CIA launched Operation PBSUCCESS, which deposed the democratically elected Guatemalan President Jacobo Árbenz and ended the Guatemalan Revolution.The coup installed the military dictatorship of Carlos Castillo Armas, the first in a series of U.S.-backed dictators who ruled Guatemala.Guatemala subsequently plunged into a civil war that costed thousands of lives and ended all democratic expression for decades.