I‘ve been told that originally imperialism was focused on trade and commerce, whereas by the Scramble for Africa, colonizers were keen to actually subdue and control conquered people’s lives. Yet I struggle to comprehend some of the subtler differences. Where does the policy of “settling with the mother country’s own people” come into play? Wasn’t economic manipulation a huge part of 19th century colonialism? Wasn’t straight up conquest of foreign climes common practice in the 16th and 17th century Americas?
Sorry for getting to this one so late, work keeps getting in the way. I'll also have to make a digression and focus mainly on the Scramble for Africa when it comes to describing New Imperialism, as it's the subject I'm most familiar with compared to India, Indochina, and SouthEast Asia.
'Old' and 'New' Imperialism don't differ much in terms of their end goal, mainly seizure of natural resources and settlement of colonists from the homeland to the new territories. What differs mainly is the resources Western European nations were after, and the tools they had to expand.
Lets tackle resources first. Colonization of the Americas initially sparked wide-eyed opportunists seeking gold and silver, which was indeed found, mined, and carted back to the homeland to provide immense boosts to the Spanish treasury in particular. Other resources exploited eventually settled on agricultural products, cash crops. Tobacco, Cotton, Sugar, and Cocoa were all New World goodies that could be grown, refined, and resold for immense profit in a pre-industrial European economy.
When it comes to Africa, and South Asia during the age of New Imperialism, the European powers were now in the full swing of the Industrial Revolution. While cash crops were still valuable products, the resource needs of industrial economies now changed to require new resources. Iron, coal, and later rubber and oil became major incentives for European expansion, while other resource classics like diamonds, silver, and gold to be found in Africa added to the incentive.
Now lets talk about the tools. When it came to the colonization of the New World, Old World diseases was a weapon stronger than any musket or cannon when it came to European dominance of the Western Hemisphere. The introduction of Smallpox, Cholera, and other Old World pathogens left much of the New World virtually empty as Europeans expanded westward as upwards of 80-90% of Native populations would die as a result of diseases they never knew exposure or immunity too.
When it comes to Africa though, you could say the situation was almost reversed. European empires rarely ever extended their control beyond the coastline of West and Southern Africa during the age of 'old' imperialism as diving further inland exposed Europeans to diseases like Malaria and Yellow Fever, making settlement of inland Africa a useless endeavor. As a result, European powers negotiated with native African states to trade for what the European powers needed from Africa, namely slaves during the height of the Transatlantic Slave Trade.
The Industrial Revolution however, led to a few key advancements that made colonization of Africa possible, and much more rapid than the colonization of the Americas. First was quinine, an effective treatment for malaria discovered by French chemist Pierre Joseph Pelletier in the 1830s. With an effective treatment against the primary barrier to European settlement, inland expansion was now possible. Next was new developments in weapons technology to overcome native African armies and resistance. The needle gun, bolt-action rifles, and most famously, the maxim machine gun greatly increased the firepower available to European armies.
The speed in which these colonization efforts took place was also unprecedented compared to older colonization efforts. Even 300 years after Europeans first arrived to settle the Americas, vast swaths of the New World remained completely unexplored, with settlement efforts still taking place as late as the early 1900's in cases like Oklahoma and further regions of the Western United States. When it came to the Scramble for Africa however, the entire continent was cleaved and carved by the Great Powers of Europe within a single generation, as shown here.
Another facet of New Imperialism, that you can say runs contradictory to the search for resources and profitability, was national prestige edged on by Nationalist elements within the Great Powers of Europe. Whether it was conquest to "civilize" native tribes as the conquering powers would put it, spreading Christianity, or spreading commerce, the conquest of new territories was seen as a boost to the prestige of the nation and by extension, the nation's people, and quickly became what this event in history implies, a scramble for new territory in order to boost the nation's image. Nationalism stoked the need for the expansion of Empires to the point that the prospect for resources of profitability of the colonies took a back seat to taking land for the simple purpose of taking land, even if it was mostly useless territory, and requiring more funds to administer the new lands than the revenue it was generating, eventually factoring into the decolonization efforts post-WWII.
If you want to read further into how the industrial revolution kicked imperialism into high-gear and the consequences of it, I'd recommend the Colonialism in Africa 1870-1960 by L. H. Gann, Peter Duignan, and Victor Witter Turner. It's a very, very dry read in my opinion, but it covers the bases.
