Sado bugyō (佐渡奉行) were officials of the Tokugawa shogunate. This commissioner was responsible for administration of the mining operations at Sado.
Appointments to this prominent office were usually fudai daimyō, but this was amongst the senior administrative posts open to those who were not daimyō. Conventional interpretations have construed these Japanese titles as "commissioner" or "overseer" or "governor."
Sado island is the sixth largest in the Japanese archipelago. It is located in the Sea of Japan off the west coast of Echigo province in northwest Honshu. For much of its pre-modern history, exiles were banished to the island.
The gold mine
In 1601, gold was discovered at Aikawa (相川) This vein was mined vigorously; and Sado's gold mine developed into a major source of revenue for the Tokugawa shogunate, producing approximately 100 tons of ore annually until the mid-18th century.