This thesis is a study of social and political relations on the Niger Bend in the century after the Moroccan conquest of the Songhay Empire in 1591. The first section discusses the primary and some of the secondary sources used in the study. Part 1, deals with the ecology of the Niger Bend and the background to the conquest. Chapter One examines the boundaries of desert, river, sahel and savanna and the physical limitations climate and geography placed on transport of goods, men and information. Chapter Two considers the ecology of the region: first in general, as it affected the life of the various ethnic and occupational groups, where the question of identity or fluidity of the ethnic group becomes a theme; then in greater detail as each of the main regions of the area is examined as a historical and geographical entity. The Third Chapter looks at the Songhay and Moroccan background to the conquest with an emphasis on the military organization of both sides. In Part II, I consider the formal history and structure of the pashalik from the conquest in 1591 to around 1700. Chapter Four is primarily on the events of the first decade, the fall of the Songhay state, the limits placed on the development of the pashalik by the early campaigns and the factors which made it possible to remain in existence. Chapter Five examines the administrative structure of the state in the context of the boundaries already drawn for the pashalik by limitations on manpower and the process by which Moroccans, Moriscos and Renegades became Arms; inasmuch as the purpose of the pashalik was to tap the wealth of the Sudan, taxation and booty are considered as alternative sources of wealth or mainsprings of political action. Chapter Six carries the history of the pashalik in relation to its immediate neighbours up to the the period of Tuareg incursions at the end of the century; the history of the pashalik auggests that, though a military state, war was not generally fought for economic benefit. Chapter Seven examines the question of state structure in specific relation to the tibshýit, i. e. the powers and methods of choosing a pasha, the problem faced by the pashalik in the Sudanese context of the need to legitimize its power, the attempts over the period to set up new forms of power structure and the factors behind their failure. Part III examines new economic and social trends over the period. In Chapter Eight which deals with the Trans- Saharan trade the old concepts of what happened to trade in the seventeenth century is reexamined; in particular a new periodization is suggestedy specifically, a crisis and shift of trade routes away from the Niger Bend in the middle of the century, followed by a revival after around 1660. In Chapter Nine, this periodization is related to cycles of drought and climatic change over the period, the rise of new nomad confederations, their increasing encroachment an the sedentary areas of the Niger Bend and, the beginnings of the organization of a 'pillage mode of production', an economy based on systematised plunder, an the Niger Bend. The last chapter deals with the of the Arma as an ethnic group becoming more directly involved in land and trade and examines the phenomenon of banditry. A final section considers more generally the interrelationship between Arma and Songhay.