There is an evolutionary bias in the anthropological view of political development, a bias that makes it seem obvious that political forms should have moved from the simple to the complex. Thus, “chiefdoms” necessarily arose out of acephalous structures such as “bands,” usually in response to similar economic conjunctures, such as a rise in trade. And the chiefdom, unless mired in evolutionary stagnation, necessarily moved in the direction of the “state.” This view of political complexification is perhaps not unrealistic in the very long term, but it becomes misleading when we extend it to the formation of actual middle-range polities in a particular ethnographic area. If the grand evolutionary scheme had indeed been working itself out uniformly over the centuries, there should have been very few small-scale polities in the world by, say, the nineteenth century, and they should all have been of very ancient vintage. Yet, when we look, for example, at Africa in recent times, we find it full of small scale polities whose formation usually dates back but a few centuries and often less.

I have argued elsewhere (Kopytoff 1987) that most of the African polities we know did not evolve out of simpler forms. To the contrary, they sprang out of more complex polities, having grown out of settlements of immigrants from chiefdoms and kingdoms, immigrants who had moved into the “internal frontiers” that lay at the fringes of fully formed polities. To these settlers, the frontier represented an institutional vacuum – an area that was out of the reach of established polities, or was entirely empty, or was under the uncertain sway of weak local hegemonies.