No scholars dispute the harm done to the enslaved people but the effect of the trade on African societies is much debated, due to the apparent influx of goods to Africans. Proponents of the slave trade, such as Archibald Dalzel, argued that African societies were robust and not much affected by the trade. In the 19th century, European abolitionists, most prominently Dr. David Livingstone, took the opposite view, arguing that the fragile local economy and societies were being severely harmed by the trade.
Though the negative effects of slavery on the economies of Africa have been well documented, namely the significant decline in population, some African rulers likely saw an economic benefit from trading their subjects with European slave traders. With the exception of Portuguese controlled Angola, coastal African leaders "generally controlled access to their coasts, and were able to prevent direct enslavement of their subjects and citizens." Thus, as African scholar John Thornton argues, African leaders who allowed the continuation of the slave trade likely derived an economic benefit from selling their subjects to Europeans. The Kingdom of Benin, for instance, participated in the African slave trade, at will, from 1715 to 1735, surprising Dutch traders, who had not expected to buy slaves in Benin. The benefit derived from trading slaves for European goods was enough to make the Kingdom of Benin rejoin the trans-Atlantic slave trade after centuries of non-participation. Such benefits included military technology (specifically guns and gunpowder), gold, or simply maintaining amicable trade relationships with European nations. The slave trade was therefore a means for some African elite to gain economic advantages. Historian Walter Rodney estimates that by c.1770, the King of Dahomey was earning an estimated £250,000 per year by selling captive African soldiers and enslaved people to the European slave-traders.
Both Thornton and Fage contend that while African political elite may have ultimately benefited from the slave trade, their decision to participate may have been influenced more by what they could lose by not participating. In Fage's article "Slavery and the Slave Trade in the Context of West African History," he notes that for West Africans "... there were really few effective means of mobilizing labour for the economic and political needs of the state" without the slave trade.
In 2009, the Civil Rights Congress of Nigeria has written an open letter to all African chieftains who participated in trade calling for an apology for their role in the Atlantic slave trade: "We cannot continue to blame the white men, as Africans, particularly the traditional rulers, are not blameless. In view of the fact that the Americans and Europe have accepted the cruelty of their roles and have forcefully apologized, it would be logical, reasonable and humbling if African traditional rulers ... [can] accept blame and formally apologize to the descendants of the victims of their collaborative and exploitative slave trade."