Ivan Gladstone Van Sertima was a Guyanese-born associate professor of Africana Studies at Rutgers University in the United States.He was best known for his Olmec alternative origin speculations, a brand of pre-Columbian contact theory, which he proposed in his book They Came Before Columbus . While his Olmec theory has "spread widely in African American community, both lay and scholarly", it was mostly ignored in Mesoamericanist scholarship, or else dismissed as Afrocentric pseudoarchaeology or pseudohistory to the effect of "robbing native American cultures". Wikipedia