At one time, the Alur had begun to develop specialized political institutions, but they remained embedded in the extended kin-based structure of segmentary lineages through which political processes also were expressed. The ruling lines of Lwo descent reached their present territory some three or four centuries ago, as part of a larger Nilotic migration from what is now Sudan. They gradually established dominance over small groups from other ethnic groups (Okebo, Madi, Lendu) and incorporated them into a new society. This dominance seems to have been established with little or no actual warfare, by employing peaceful methods that provided a somewhat larger scale of organization, by instituting more effective methods of dispute settlement, and, above all, by supplying the nonmaterial means of production in the mystical form of rainmaking, which attracted the support and allegiance of all. Such mystical powers are held in exclusive possession by the hereditary heads of the principal Lwo lineages, which reached different parts of the country by various routes. With the passage of time and demographic growth, the major lineages themselves segmented, and the mystical services of rainmaking and sacred kingship proliferated and expanded to cover an ever larger territory.
Two chief mechanisms led to this proliferation and expansion. The king would send an unruly, troublesome son out to live among as yet unincorporated groups of non-Alur. The son would go with followers and cattle, providing feasts and receiving gifts in return, setting up a new cycle of economic and marital exchange and redistribution, mediating and arbitrating disputes, and providing a channel of privileged access to the rainmaking powers of the king, his father, which eventually became powers exercised by himself and his heirs in their own right. Alur lineages and clan sections sometimes petitioned the king to send them one of his sons to be their local ruler, making them more highly respected by neighboring groups, who might also have done the same, and providing them with the same mystical, political, and economic services. These rulers did not endeavor to eliminate interpersonal violence altogether. Compensation for offenses, including homicide, could be sought by the men of the lineage concerned, and lineages could even fight if they failed to agree. To continue fighting was an offense against the king's stool (i.e., his mystical authority), however, and had to be resolved by payment of a fine. If a group refused to pay, the king's only ultimate recourse was to call other groups to join with him in plundering the offenders. This was a rare but feared deterrent.
In sum, the segmentary state was characterized by an elementary political sovereignty that was restricted to a small, central-core domain, but a general ritual suzerainty spread out more widely. This relationship of sovereignty and suzerainty at the center was repeated on a smaller scale at the peripheral centers that were derived from it, creating a pyramidal structure.