This study examines the complex history of slavery in East Africa, focusing on the area that came under German colonial rule. In contrast to the policy pursued at the time by other colonial powers in Africa, the German authorities did not legally abolish slavery in their colonial territories. However, despite government efforts to keep the institution of slavery alive, it significantly declined in Tanganyika in the period concerned. This book highlights the crucial role played by the slaves in the process of emancipation. This book is divided into three parts. The first explores the rise of slavery in Tanganyika in the second half of the nineteenth century when the region became more fully integrated into the world economy. This is followed by an analysis of German colonial policy. The authorities believed that abolition should be avoided at all costs since it would undermine the power and prosperity of the local slave owning elites whose effective collaboration was thought to be indispensable to the functioning of colonial rule. The final part recounts how slaves by their own initiative brought the 'evil institution' to an end. This comprised both highly disruptive moments of wholesale flight and, depending on the possibility of escape and individual circumstances, more subtle changes in servile relationships. This study is of interest not only to historians of East Africa, but makes a contribution to the more general debate about the demise of slavery in the continent.