Introduction

The Tanzanian climate is influenced by Indian Ocean monsoons, which annually bring one short and one long rainy season. As a result of an uneven distribution of water, arable land, and economic opportunity, the Tanzanian society is most densely settled on the islands of Zanzibar and Pemba and near the borders of the mainland. Over 70 percent of all Tanzanians live in the rural areas and with their urban counterparts belong to more than 120 ethnic groups. Most of these are small, the largest accounting for only 13 percent of the total population. Following the Zanzibari revolution of January 1964, Tanganyika and Zanzibar merged to form the United Republic of Tanzania. In discussions of Tanganyika that are not historically specific, the terms mainland Tanzania or the mainland will be used. Zanzibar and adjoining Pemba will be collectively referred to as “Zanzibar,” except where distinctions must be made between the two islands.