Is one group of people justified in taking over the trading and commercial networks from other groups of people, such as the Europeans did when they entered the Indian Ocean in their ships?

Yes that's true; this happened in Indian Ocean trade

Explanation:

Indian trade on the ocean has been a major factor in East / West transactions all along with the past of which different trading routes are often known as the Monsoon Market.

In the 1500s, when Portugal conquered and sought to attempted to make its own benefit, Indian Ocean Trade start with small Treaties across 800AD, declining

The intention of Vasco Da Gama was to find a path from Portugal to Europe, Africa and then to India, by sailing across. For several years, European countries have purchased Asian products via other, harder paths.

Vasco da Gama as well as other Europeans, who toured the city-states of the Swahili Mountains, also preserved journals describing both port cities ' wonders - and eventually their brutal devastation by the Portuguese settlers.

So obviously the records of stock transactions made through the Indian Ocean trade network have been stored by African and Asian businesses and governments.