Though Columbus was not the first European explorer to reach the Americas (having been preceded by the Norse expedition led by Leif Ericson in the 11th century[4][5]), his voyages led to the first lasting European contact with the Americas, inaugurating a period of European exploration, conquest, and colonization that lasted for several centuries. These voyages had, therefore, an enormous impact in the historical development of the modern Western world. Columbus spearheaded the transatlantic slave trade and has been accused by several historians of initiating the genocide of the Hispaniola natives. Columbus himself saw his accomplishments primarily in the light of spreading the Christian religion.[6]