2oo AFRICAN POLITICAL SYSTEMS
unit as long as these smaller groups are subordinated to it, i.e. derive their authority from the central government. In the case of the Kavirondo tribes, however, no such definition of the political unit on the basis of internal and external sovereignty can be given. As regards submission to political leadership, the largest groups, both among the Logoli and the Vugusu, are the exogamous, patrilineal clans1 or clan groupings, consisting of one larger and several smaller clans, but not the whole tribal society. The tribal unit is marked by the belief in the common descent of all clans from one remote tribal ancestor, Murogoli and Muvugusu respectively, and by the occupation of a continuous stretch of territory. In addition, there are numerous institutionalized forms of co-operation and interdependences between the different clans of the tribal group which distinguish inter-clan relations from inter-tribal relations, but there is no tribal authority which overrules clan authority, either in its dealings with foreign tribes or in the management of its internal affairs. In terms of the definition given above, the clan would thus have to be regarded as the only political unit.
A number of considerations, however, make it seem more adequate to widen the definition of the political unit so that it comprises the tribal unit rather than the clan. In the first place, the fact that clans are exogamous and that marriage is regulated in such a way that all clans of the tribal group intermarry, establishes a close connexion between the clans. The kinship bonds, maintained between every member of the clan and his maternal kin as well as his affinal relations, are so numerous and so strong that they establish bonds between the clans which, as we shall see, are in many ways as binding as if there were a central authority overruling that of the clans. Furthermore, the cult of a common tribal ancestor, to whom the Logoli sacrifice on a tribal scale at regular intervals, and the performance of the circumcision rites on a tribal scale create a feeling of unity which serves as a sanction for close co-operation in all matters affecting the tribal group.
The concept of 'political structure', likewise, requires a wider definition than is customary to become applicable to Kavirondo
1 The clan (oluhia, luyia) is named after its real or supposed founder and its members tend to form a territorial unit. The various characteristics of the clan are discussed later on in this chapter in their respective contexts.