Answer:
I think the answer is physical property.
The African culture was matrilineal, had an elaborate system of social rank and that worshipped many gods. The Africans were already engaged in slavery because they responded to the demand form wealthy families in the Mediterranean who wanted black men and women as domestic servants. They provided slaves for labour shortage in Europe. Slavery began to increase because of sugar cultivation.
It occurred chiefly due to the economic interventionism of the Japanese government and partly due to the aid and assistance of the U.S. aid to Asia. After World War II, the U.S. established a significant presence in Japan to slow the expansion of Soviet influence in the Pacific.
