It’s described in every anti-colonial text. A select and usually tiny number of the existing ruling class or groups chosen to be the ruling class of the colonized people are elevated to the local bourgeoisie to legitimize the colonial regime but also individual opportunists who get elevated to “preferred subjects” and act on behalf of the metropole, won’t be at the wrong end of the colonizer’s gun (at least initially). They also see their special status as a means to gain and control wealth and consolidate power locally even though they as a class will never attain parity with the colonizers.