Complex sentence: He learned about the continuing existence of slavery in North Africa in 1993, and left his (consulting) career a year later to found the American Anti-Slavery Group, together with African human rights activists Mohamed Athie of Mauritania and David Chand of Sudan.
Split into simpler sentences: He learned about the continuing existence of slavery in North Africa in 1993. He left his consulting career in 1994 to found the American Anti-Slavery Group with African human rights activists Mohamed Athie of Mauritania and David Chand of Sudan.