In what ways did European colonizers expand their colonies?

They expanded their colonies by:

Transportation Communication Warfare Ethnic and Cultural division

Explanation:

Transportation:

It played a vital role as without ships it wouldn't have been possible to travel around the world ... Later, railways also became equally important.

Communication:

Communications were important for colonizers for organizing and coordinating among themselves and to take order from the home.

Warfare:

Colonizers used to have large armies, latest technologies and advance weapons which gave them a huge advantage when waging war on the local population.

Ethnic and Cultural Division:

Colonizers used the ethnic and cultural diversity of the population to their advantage, which allowed them to use hierarchical relations for their purposes and also increased their supporters.