This article examines the evolution of social inequality through tests of the influence of political, economic and social factors. “Analysis of comparative data shows that while some dimensions of the stratification system (such as measures of social complexity) exhibit a monotonic trend of increasing inequality with level of technology from the hunting-and-gathering to the agrarian type, others (such as measures of freedom and sexual inequality among males) exhibit a pattern of “agrarian reversal” in which inequality increases from the hunting-and-gathering to the advanced horticultural type but then declines with the agrarian type” (292).