Kokudaka

Kokudaka is a historical Japanese measure of a domain’s wealth and revenue, defined as the assessed annual output in koku of rice that a domain was considered capable of producing. One koku is traditionally understood as the amount of rice needed to feed one person for one year, commonly cited as about 180 liters. The kokudaka functioned as a fiscal and political gauge rather than a simple land area measurement.

In practice, kokudaka determined a daimyo’s status within the Edo period han system. The higher a domain’s kokudaka, the greater its prestige and the larger its military and administrative obligations, including the sovereign’s taxes and, in many cases, the obligation to maintain samurai stipends and participate in sankin-kotai (alternate attendance) duties. The value was used to classify domains, allocate duties, and regulate governance across the shogunate.

Calculation and scope: Official surveys and annual reports assessed the domain’s potential harvest, typically expressed in koku per year. The system accommodated improvements or losses in productivity, but it emphasized expected output rather than actual land area alone. Land quality, climate, and geographic features meant that large territories could have modest kokudaka, while smaller but highly fertile areas might yield a higher figure.

End and legacy: The han system and its kokudaka framework persisted until the Meiji Restoration, when the domains were replaced by prefectures in 1871 and the kokudaka-based fiscal model was dismantled. The term koku remained as a historical unit for rice production, and kokudaka is frequently referenced in historical studies of Edo-period governance and economy.