As many as three million people may have been taken as slaves from this general region during the three centuries that the transatlantic slave trade operated. It is not known how many people were taken as slaves by intertribal wars or Muslim traders before the transatlantic slave trade began. Most of those taken were sold by other Africans to Europeans: some were prisoners of intertribal wars; some were victims sold because of unpaid debts, and many others were simply victims of kidnapping.