Abstract. Pemba, one of Tanzania’s three major offshore islands, has long been considered a peripheral, rural place, the agricultural ‘breadbasket’ of nearby Mombasa. This image derives from the post-A.D. 1500 period when Pemba indeed was the location of much agricultural production for export, and especially from the 19th and 20th centuries, when, with the Omani capital of power just south on Zanzibar, Omani settlers created a plantation economy on Pemba. The reputation of Pemba as peripheral to Swahili centers of power in those later centuries is complicated by an increasingly rich archaeological understanding of the island’s pre-15th-century towns and villages. What emerges from archaeology is a political, economic, and religious landscape of competitive polities perched on the island’s coastline, looking out at the larger Swahili and Indian Ocean worlds. Our last decade of work on Pemba has helped illuminate the life history of an urban polity called Chwaka and its nearby forerunner, the large village of Tumbe. In this paper we explore transformations over some eight centuries of town life, contextualized against what we know from regional archaeology and history. Far from being a dominated agricultural periphery, Pemba Island earned a position among powerful coastal centers before exigencies changed and it took its secondary role of more recent centuries. Our study allows us to draw on three lines of evidence to support our argument: the scale and richness of Tumbe; Chwaka’s trajectory of growth through attraction of settlers from its own hinterland; and the later town’s strong economy and investment in elaborate religious architecture.