As you saw in the video, the Netherlands has been trading slaves for a very long time (200 years). They made a lot of money from this. First they went to Africa to get slaves. They took those slaves to other countries such as Suriname and Curaçao. When Brazil was a colony from the Netherlands, they bring also slaves to Brazil to work there on the plantages. You can see on the map that Suriname and Brazil located close to each other. The two countries are also both on the coast.
Video
A video about the slavery in the 17th centrury
https://schooltv.nl/video/welke-rol-speelde-nederland-in-de-slavernij-nederlanders-gingen-naar-landen-in-afrika-en-maakten/playlist/356/
Als je deze link kopieert kom je bij de video