The document summarizes the slave trade that occurred between Europe and Africa beginning in the mid-15th century. Europeans expanded their empires in the new world but lacked a workforce, so they began transporting Africans captured from West Africa to work as slaves. It is estimated that 15 million people were transported as slaves, with many dying during the journey packed tightly into ships. Questions remain about why black Africans were specifically targeted for slavery and how exactly they were originally captured.