W. Wayne Farris has developed the first systematic analysis of early Japanese population, the role of disease in economic development, and the impact of agricultural technology and practices. In doing so, he reinterprets the nature of ritsuryo institutions.

From tax and household registers, law codes, and other primary sources, as well as recent Japanese sources, William Wayne Farris has developed the first systematic, scientific analysis of early Japanese population, including the role of disease in economic development. This work provides a comprehensive study of land clearance, agricultural technology, and rural settlement. The function and nature of "ritsuryō" institutions are reinterpreted within the revised demographic and economic setting.
Farris's text is illustrated with maps, population pyramids for five localities, and photographs and translations of portions of tax and household registers, which throw further light on the demography and economy of Japan in the seventh, eighth, and ninth centuries.