Complex sentence: Despite the successes against the Simba rebels, Tshombe's prestige was damaged by the use of white mercenaries and western forces, lost the support of Kasa-Vubu and was dismissed from prime minister in October 1965.
Split into simpler sentences: Despite the successes against the Simba rebels, Tshombe's prestige was damaged by the use of white mercenaries and western forces. He lost the support of Kasa-Vubu and was dismissed from the post of prime minister in October 1965.