What role did Africa play in the development of slavery in the New World?

African participation in the slave trade

Africans played a direct role in the slave trade, selling their captives or prisoners of war to European buyers. The prisoners and captives who were sold were usually from neighbouring or enemy ethnic groups.

then its a law the end

powers  are  denied  to the  national governmentin three distinct ways: some  powers, such as the  power  to levy duties on exports or prohibit the freedom of religion, speech, press, or assembly, are expressly  denied  to the  national government  in the  constitution.