São Tomé and Príncipe played an important role in the Atlantic slave system, but not primarily as a major departure point supplying enslaved people to the Americas.

Instead, the islands were primarily an early Portuguese slave-based plantation colony, a transit and trading point, and a place where enslaved Africans were forced to work.

Beginning in the late 1400s and 1500s, the Portuguese established sugar plantations on São Tomé, relying on enslaved labor, much of it drawn from the nearby Central African mainland, especially from regions now part of Angola, the Democratic Republic of Congo, and the Kingdom of Kongo.

The islands became one of the earliest plantation economies in the Atlantic world and helped shape systems later used in Brazil and the Caribbean.

Some enslaved people passed through the islands before being transported elsewhere, but São Tomé itself was not a major source of enslaved people. The islands’ population was relatively small, so they could not function as a massive export region like Angola or the Bight of Benin.