>>17967877
The whole region, including Belgium and Holland, were the wealthiest part of the Europe in the medieval and renaissance period. Out of the two, the one that got the colonies became more wealthy.

After that, the nearby state of Britain (already quite wealthy for similar reasons) got very far ahead after they had colonies in America and India sending revenue home, and after resources from those places began to feed their industries in Britain.

The colonies came as an investment in increasing power.