The Pangani Valley region in northern Tanzania is dominated by an arc of highlands that stretch from Usambara to Arusha. In this region, ecotonal variations in environments have shaped—and were in turn shaped by—cultural, political, and economic forces. Since the early 18th century three major events and shifts in regional and world systems dynamics affected significant economic and political changes on the highlands. First, the international ivory and slave trade increased in volume and organization; second, this led to an expansion of specialized pastoralism through an increased availability of cattle in the region; and third, at the end of the 19th century the region was included into a colonial state.
The populations of the highlands were all organized into patrilineages and patriclans. Sometime in the late 1600s or early 1700s, several of the kinship-based, highland communities developed into chiefdoms of varying sizes and degrees of stratification. The ability of a chief to maintain a rudimentary administration and political power depended on the possession of wealth in the form of livestock, rights in persons, and rights in land. A part of household production in the form of crops, livestock, and beer was transmitted from farmers to chiefs as tribute. The most valued part of the tribute was cattle, which the chief needed to build a large family, to obtain debt-clients, and as gifts to lineage heads and the young men who served as warriors. Thus, the political cohesiveness of chiefdoms was ultimately contingent on the chiefs’ abilities to control the flow of cattle and to supply these to local lineage heads and subchiefs. The political strategies that maintained stratification in the highlands varied between the different areas. On Kilimanjaro, politics among the Chagga was based on marriage arrangements, while in North Pare it was control of land and irrigation that were used for political purposes, and in South Pare and Usambara control over rain-making rituals provided the cultural justification for the centralization of power. Cattle were the main resource for implementing culturally defined political strategies. Their importance was exacerbated during the 19th century when increased political turmoil caused by participation in the coastal trade opened new avenues for access to wealth outside the kinship-based networks. As a result, new actors entered into competition for cattle and political power that resulted in increased tribute demands, as well as raiding and warfare.
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