The Portuguese empire in the Indian Ocean was a traditional thalassocracy which had extended its reach to every major choke point in the Ocean. Trade in the area corresponded also to a traditional triangular model whereupon small manufactures would be brought from Europe and traded in Africa for gold and several items, then these would serve to purchase spices in India proper which were then brought back to Europe and traded at immense profit which would be reinvested into ships and troops, to be sent eastw

Source: Dutch–Portuguese War – Wikipedia