The slave trade recommenced in 1455 in Africa. The Pope gave justification to enslave non-Christians in a papal bull.[Citation Needed] It became an important part of Africa's economy. It did not come to an end until 1800-1865 with the work of Christians; William Wilberforce and John Wesley.[Citation Needed] The United States passed the 13th Amendment in response to it.
The "slave trade" was preeminently neither a trade nor an activity initiated by the victims. It was not merely a mechanism to answer the labor needs of the Americas and the Caribbean but an example of deep moral and ethical failing that relied upon the belief of white racial superiority to sustain it.
World History Lecture Eight can be used for more information.