Along with distilling rum and growing sugar, this practice made up the third side of the "triangle trade.
John Kimber was acquitted of murder for actions while participating in this practice. A series of letters by Afonso I requested Joao III to curtail this practice among his subjects. Kingdoms which benefited from this economic activity included Oyo and Dahomey. Olaudah Equiano and (*) William Wilberforce fought against this practice, and John Newton wrote the song "Amazing Grace" after becoming disillusioned with this practice. Along with distilling rum and growing sugar, this practice made up the third side of the "triangle trade." The "middle passage" was part of, for 10 points, what practice of buying and selling humans?
John Kimber was acquitted of murder for actions while participating in this practice.
Atlantic slave trade (accept close equivalents such as buying slaves or selling slaves or transporting slaves; prompt on slavery and equivalents; anti-prompt [ask for less specificity] on middle passage before mention)