the characteristics of a frontier society. During the first millennium A.D. a
"tidal frontier" of mixed farmers had founded a series of settlements south
of the Limpopo. During the second millennium, mixed farmers had been
expanding from those established settlements along a myriad of "internal
frontiers" into lands previously occupied, if at all, by hunter-gatherers or
pastoralists. Old chiefdoms split and new chiefdoms arose, and in due
course they too threw off splinter groups to form the nucleus of new
chiefdoms. 84 The entire process hinged on the availability of fresh land. By
the end of the eighteenth century, the population on the land east of the
twenty-inch rainfall zone was reaching its limits in relation to the economic
system. The precondition for the continuation ofthe frontier dynamics was
beginning to collapse, with dire consequences, which V\Teshall describe in
chapter 3.
30