For a long time, a large part of the collection on slavery was held by the Royal Tropical Institute. The oldest objects were compiled at the time the museum was still located in Haarlem and was called the Colonial Museum. Some of the objects originate from the collection of Natura Artis Magistra (Artis), the Amsterdam zoo, and were transferred to the Colonial Museum when the latter relocated to Amsterdam at the beginning of the twentieth century.
Religion is an important theme in the collection on slavery. The old beliefs to which the slaves had adhered in Africa, served as a basis for new religions that came into being among them in the Americas. Sometimes the slaves had to worship in secrecy since their Christian owners were opposed to the services they held.
There are still strong African traits in a number of these religions, for instance in the Winti religion in Surinam. The collection on slavery includes some objects related to the Winti cult that date from before and after the abolition of slavery (Van Breugel Collection, acquired via Artis). Other religions became more a mixture of traditions: Christian on the outside and African on the inside, making it easier for them to survive. Examples of such cults are Vodou in Haiti, Santería in Cuba as well as Umbanda and Candomblé in Brazil. The objects connected with these religions are of a much more recent date, but they too are part of slavery's heritage.