In this essay, the author attempts to clarify the monetary policy and features of domain-governing of Mori-shi 毛利氏 in the Sengoku 戦国 period, by taking notice of the kind of coin and numeral value of itself, and reexamine the historical meaning of Sōkoku-Kenchi 惣国検地, a whole domain land survey, at the Tenshō 天正 period.
The monetary policy of Ōuchi-shi 大内氏 was prohibition of Erizeni 撰銭, a selecting refined coins, in the domain, while he personally exerted himself to acquire Seisen 精銭, refined coins, and so it was confirmed that he used them in the distant trade. And at the same ages, the sums of "Seisen"「精銭」 which was estimated by the "Seisen", had already come into existence as the standard sums, and they played the important role of domain-governing not only for Ōuchi-shi but also for Mōri-shi.
Mōri-shi had the basic policy that he followed the former powers on governing the new occupied domain. Similarly has he succeeded to the standard sums which had already come into existence in the former ages, as the sums of "Kosen"「古銭」, and used them as a basis of domain-governing. But, these standard sums were primarily several ones which had their own local features and different reasons of birth, so the actual state was the coexistence of uneven standard sums, as it were.
Therefore, Sōkoku-Kenchi which Mōri-shi has carried out in whole domain-wide with this historical background, was important policy. That is to say, at this Kenchi has Mōri-shi adopted "Kokkan"「石貫」 system which was composed of the standard coin "Chan"「鍛」 and the standard measure "Kyōmasu"「京桝」, and materialized the quantitative grasp of lands by the unitary standard for the first time. In this way, has Mōri-shi finally established the unitary Chigyō 知行 system and Gunyaku 軍役 system in whole domain-wide.