This is the story of a world whose territories and own frontiers were built by the slave trade. A world where violence, subjugation and profit imposed their routes. The history of slavery did not begin in the cotton fields. It is a much older tragedy, that has been going on since the dawn of humanity. From the VIIth century on, and for over 1,200 years, Africa was the epicenter of a gigantic traffic of human beings traversing the entire globe. Nubian, Fulani, Mandinka, Songhai, Susu, Akan, Yoruba, Igbo, Kongo, Yao, Somali… Over 20 million Africans were deported, sold and enslaved. This criminal system thrived, laying the foundations of empires around the world. Its scale was such that for a long time, it has been impossible to relate it comprehensively. And yet, it raises a fundamental question: how did Africa end up at the heart of the slavery routes?