In order to decide if colonialism in various parts of the world (and the galvanization by specific countries toward colonialism) is similar enough to group together, one must first pause to consider what defines colonialism. One source explains:
Colonialism is a practice of domination which involves the subjugation of one people to another.
This is also referred to as settler colonialism. However, it is also pointed out:
One of the difficulties in defining colonialism is that it is hard to distinguish it from imperialism.
Imperialism is also referred to as exploitation colonialism.
The term imperialism often describes cases in which a foreign government administers a territory without significant settlement.
Some sources define the two as very much the same. However, others differentiate colonialism vs. imperialism in this way: colonialism involves the subjugation of people in other countries and the immigration of settlers from the dominant nation into the nation being "colonized." On the other hand, imperialism (perceived to operate in much the same way) does not have an influx of immigrants from the dominant nation. In fact, continued domination is carried out by a limited number of people from the conquering nation.
Whether referring to colonialism or imperialism, people from the weaker country lose their independence, and very often the exportation of natural resources from stronger nation drives continued occupancy of the weaker country.
Many may see Great Britain as the one-time leader of colonization in the world:
A series of wars in the 17th and 18th centuries with the Netherlands and France left England (and then, following union between England and Scotland in 1707, Great Britain) the dominant colonial power in North America and India.
In India, for example, Britain set up trading posts along with other nations, such as the Dutch, the French and the Portuguese. Eventually, however, [continental European powers] "eventually lost all their territories in India to the British islanders." At one point, the British Empire dominated India's "princely states" by a two-thirds margin.
In Africa, King Leopold II of Belgium infiltrated the area then called the Congo (or the Belgian Congo), subjugating the people and stripping it of its natural resources, primarily ivory (in great demand in Europe), and later, rubber. His treatment of the people of the Congo was reported by newspapers and missionary groups: eventually, he was forced to release his hold on the Congo, but not after he had made millions of dollars.
Examining what became Indonesia, under the control of the Dutch government, once again, subjugation took place. The people indigenous to this country were controlled by the Dutch, segregated, and their country's natural resources exploited to allow the Dutch to "experience global prominence" with the exportation of these goods (including spices, etc.)
While the United States "won" the Philippines from the Spanish at the end of the Spanish-American War, the Philippines were still a colony of the United States, and prevented from self-rule.
In studying each situation, all seem to be similar enough to "lump" them together: other people were controlled against their will by a more powerful nation.