Population growth and concomitant agricultural intensification are often considered to be instrumental in the development of hierarchical societies. However, an examination of two 19th century states in wet tropical Africa, Bunyoro and Buganda, reveals that a shortage, rather than an abundance, of people encouraged elite control of resources. The demand for labor, primarily in the form of women's agricultural labor, may have been the motor of sociopolitical evolution. Historical, demographic, and epidemiological data demonstrate both the importance of women's labor for the development of subsistence economies and a corresponding scarcity of women in western Uganda. Thus, the development of chiefdoms and states was predicated upon the ability of leaders to attract followers in a region where arable land was abundant but required labor to clear the forest. In the sparsely settled regions of western Uganda at the beginning of the present millennium, wealth in people was the key to both subsistence and security. Examination of archaeological evidence from Bunyoro reveals some of the strategies used by elites to attract followers. Prior to the 15th century, these included the development of an international style and control of prestige goods obtained from long-distance exchange networks, control of iron production, the giving of feasts, and the exercise of ritual authority. As a result of the success of some of these strategies, several larger polities developed by the mid-15th century. Extensive systems of earthen ditches were then constructed at several sites, their construction financed by surplus production of staple foods. The earthworks served a variety of functions, with military defense being one of the least important. Nevertheless, raiding for cattle and women may have become commonplace, with the latter increasingly being treated as commodities, a status against which some women later expressed their opposition through their involvement in spirit-medium cults. The earthworks and their associated settlements seem to have been abandoned about the end of the 17th century for unknown reasons. A settlement pattern of dispersed homesteads then developed. These changes may be linked to the establishment of the Nyoro state under the Bito dynasty. Subsequent centuries witnessed the growth of the Nyoro and Ganda states spurred by competition between them and by the development of markets and the growth of long-distance trade. Despite the power of these states, much smaller polities, founded primarily upon ritual legitimacy, continued to exist. In the long term these polities might have been more stable than the larger states whose existence required continuous inputs of foreign goods and labor. However, this conclusion is conjecture because British colonialism and its aftermath intervened at the close of the 19th century.