Oematan is the ancestral house of the active rulers who acted in the name of the sacred Sonba'i. Atoni sovereignty is characteristically split into a still, potent centre and a moving, governing arm: while the Great Sonba'i sits immobile as the source of order and fertility, it is the Oematan who speaks, judges, gathers tribute and leads the war-bands. The name, 'water-source', evokes the spring from which a settlement draws life. In the dual scheme the pair reproduces the cosmic contrast of a hidden, generative principle and its visible, effective expression, so that the earthly polity restates the order that Uis Neno holds above.