United States: green cards granted to Africans 1820-2019, by country and decade

In comparison to the other continents, historical migration rates from Africa to the United States have been relatively low. While almost 400,000 Africans were forcibly taken to mainland North America during transatlantic slavery, the abolition of the slave trade in 1808 was followed by incredibly low migration rates due to widespread poverty across the continent, lack of opportunity, and restrictive migration policies in the U.S. The past two decades have seen a significant rise in immigration from across Sub-Saharan Africa, where rapid population growth, climate change, conflict, and instability have driven millions to leave the continent each year, although only a relatively small share migrate across the Atlantic to the U.S..