The Indian Ocean region is a continuum of social, economic, and cultural engagements. It is also a remarkably elastic matrix of human relations that has profoundly influenced and been influenced by global engagements. These interregional engagements raise questions of how to frame global circularities within Indian Ocean pasts. How have imbrications with other world regions affected the networks and boundaries of the Indian Ocean region? And how have Indian Ocean societies affected the wider world? To answer these questions this article traces Indian Ocean histories within global contexts between the sixteenth and early twentieth centuries. It offers a stereoscopic history of Indian Ocean Africa that appreciates Indian Ocean linkages alongside the region's global entanglements, which in turn demonstrates how Africa's Indian Ocean rim has affected and been affected by wider global relationships. The article suggests that imbrications of regional and extraregional networks do not negate the Indian Ocean's coherence or the central importance of regional linkages. Rather, it argues that such imbrications prompt alternative ways of perceiving Indian Ocean worlds: namely, as layered matrices shaped by the dual articulation of Indian Ocean rim societies.