Sentence:  By linking these sub-nationalities to cultures and by exculuding black Jamaicans from his list, he also (perhaps unwittingly) invoked the British colonial ideology that positioned laboring groups arriving in Jamaica after the abolition of slavery as <WSD>cultureful</WSD>—that is, as coming from "civilizations" with ancient text-based religions—as compared to transplanted Africans, who were positions as cultureless and therefore eminently assimilable. 
Meaning of the word marked with <WSD> tags:  Pertaining to intellectual activities.