I'm not sure what you think I suppose to mean. The economic impact of colonialism is already an active area of study. I'm just pointing out that it exists.
Well, the submission itself has a section entitled "Institutions". Institutional economics is a field of economics that studies the impact of the strength, stability and overall design of "institutions", in the widest possible sense, on economic activity. Stuff like the impact of the credibility and strength of property rights or the impact of minority rule, for instance, goes in here.
Growth theory, or rather development economics, studies how and why wealth grows. And here go ... pretty much any economic growth models. I really don't know how else to say it.
Finally, an institutional approach to development economics studies how institutions might cause nations either grow or not, depending on their institutions, and the guys who kick-started this approach were Daron Acemoglu of MIT and James Robinson, of Chicago University. They have a book on it called "Why Nations Fail", released in 2012, which has already been recommended by another commenter. Their main thesis being that certain patterns of colonialism induce certain patterns of institutions, which they call "extractive", by which a minority appropriates most of a country's wealth for itself, while setting the country on a low growth path. The classic example being a resource-based economy under either a minority or authoritarian rule.
If this all sounds really general, that's because it is. I haven't read much on institutional economics, much less on the economics of colonialism. But I know it's out there.