Beginning in the 16th century, European traders began to buy or capture people in the African continent to enslave and sell for profit. This trade began with Portugal and Spain, but it later expanded to include France, England, the Netherlands and other European countries. By the time the trading of enslaved people was finally put to an end in the 19th century, Europeans had abducted an estimated 12.5 million African people from their homelands, forced them onto ships, trafficked them to the Americas, and sold them on the auction block. Almost two million people died during transport; most of the rest were forced into labor camps, also called plantations. This extensive and gruesome human trafficking is commonly referred to as the transatlantic slave trade.

The Portuguese began human trafficking in Africa by trading manufactured goods or money for Africans who had been captured during local wars. Later, some Europeans captured Africans themselves or paid other local Africans to do it for them. Europeans traded for or kidnapped Africans from many points on Africa’s coast, including Angola, Senegambia and Mozambique. Most of the people who were enslaved by the Europeans came from West and Central Africa.

The most brutal segment of the route was the Middle Passage, which transported chained African people across the Atlantic Ocean as they were packed tightly below the decks of purpose-built ships in unsanitary conditions. This trip could last weeks or months depending on conditions and the trafficked people were subjected to abuse, dangerously high heat, inadequate food and water, and low-oxygen environments. Olaudah Equiano, a young boy who was forced into the Middle Passage after being captured in his home country of Nigeria, later described the foul conditions as “intolerably loathsome” and detailed how people died from sickness and lack of air. Approximately 1.8 million African people are thought to have died during the passage, accounting for about 15–25 percent of those who were taken from Africa.

For many enslaved Africans trafficked across the Atlantic, the port at which their ship landed was not their final destination. Enslaved people were often transported by ship between two points in the Americas, particularly from Portuguese, Dutch and British colonies to Spanish ones. This was the intra-American slave trade. No matter where they landed, enslaved Africans faced brutal living conditions and high mortality rates. Moreover, any children born to enslaved persons were also born into slavery, usually with no hope of ever gaining freedom.

This data set is the culmination of decades of archival research compiled by the SlaveVoyages Consortium. This data represents the trafficking of enslaved Africans from 1514 to 1866. All mapmakers must make choices when presenting data. This map layer represents individuals who experts can definitively place at a given location on one of at least 36,000 transatlantic and at least 10,000 intra-American human trafficking routes. However, this means the enslaved people for whom records cannot place their departure or arrival with certainty do not appear in this map (approximately 170,985 people). This map, therefore, is part of the story, and not a complete accounting. You can learn more about the methodology of this data collection here.