Characterize the relationship between europe and africa after 1450

The general relationship between Europe and Africa after 1450 was highly "extractive," in that ever since the discovery of Africa (and especially after the discovery of the New World), European nations colonized Africa in order to cultivate as many natural resources as possible. 

The transcontinental railroad provided a means of fast transportation. it cut a 6 month trip into 6 days, created jobs for many people and encouraged immigration. the homestead act played a huge role in western expansion; it allowed settlers to begin a fresh start, and gave them land in exchange for their residence for up to five years and a small fee.