The world of classical Greece was riven with conflict. The geographical division of Greek society into hundreds of independent city-states led to the most obvious form of conflict, wars between communities. Equally pervasive, however, was social conflict within individual communities. Class struggle was so endemic in Greece that a specific word, stasis was used to refer to it.
The lines of demarcation in such internal conficts were frequently too complex to be characterized simply as "rich" versus "poor." For example, at some times and places the heart of the struggle was between long-established aristocratic families and a rising mercantile class, many of whose leading members might actually be wealthier than many aristocrats. At other times (usually later, after the new rich had supplanted or been absorbed into the landed aristocracy), the conflict was more directly between the rich and the poor. Each of these was equally to be regarded as a form of stasis.
Such conflict was a driving force of Greek history. The colonizing movement of the pre-classical period was probably driven largely not by overpopulation per se, but by land shortages, which threatened to reduce much of the population to pauperdom, and thus exacerbated latent social tensions (Snodgrass, 40). But this proved only a temporary expedient, and the threat of stasis soon re-emerged. The rise and fall of tyrannies (which in Greek usage connotated any extralegal dictatorship, whether or not it was oppressive) was rooted in these class struggles.
The very different societies of Athens and Sparta, as these had taken form in the classical age, embodied two variant solutions to the problem; in Athens, what we may regard as "progressive" aristocrats opted to support the popular party and establish a democratic system, while in Sparta, the conquest of Messenia and apportionment of its land and helot population to support the Spartiates was designed to...