Nias island was officially part of Fantsur (Barus) empire in the tenth century (as it might have been earlier).
This statement is accurate according to Vereenigde Oostindische Compagnie's notes.
At the end of 1855, The Nias Expedition was launched by Netherlands to expand their territory to plant spices on land and to build harbors at the beach.
Occupying Nias would make it easier for the Netherlands to control the trade route at west coast of Sumatra.
If spices grew well, the Dutch East Indies would be able to build a twinning harbor city like Sibolga or Barus.