Political map of Sub-Saharan Africa 24 August 1964 (Simba Rebellion): In 1964 the United Nations withdrew its troops from the Congo (United Nations Operation in the Congo), exposing the nation to a new outbreak of unrest as the Soviet-backed Simba rebels rose up in the east (Simba Rebellion). Despite rapid gains, the Simba rebels were crushed in late 1964 with the help of a US-backed Belgian intervention (Operation Dragon Rouge).