In the strictest sense, Africa, Arabia, Persia, and India are not parts of the same cultural zone. Historically, foreigners, particularly Arabs, have had closer relations with the worlds of the Mediterranean and the Middle East than with Africa, and for their part most Africans have had few direct interactions with Asians. Yet Mother Nature, in the forms of wind and water, has provided the means for an interface between East African and western Indian Ocean shores that long has helped make the peoples of these regions close neighbors. For at least 2000 years trade goods have passed with the monsoons between African and Asian ports. While these regions have shared an ocean highway that has facilitated such material exchanges, differences in their respective hinterlands have made Arabia, Persia, and India exporters of finished wares and Africans suppliers of primary commodities. Hinterland conditions also have contributed to the movement of free persons and ideas from Asia, especially Arabia, to East Africa, while slaves have passed in the opposite direction. For East Africa, the periodic arrivals of Asian settlers had significant social and ideological consequences. It is the purpose of this paper to assess these connections in detail, especially as they affected East Africans.