In the 'Four Fujiwara brothers government' era, the finance under the Ritsuryo codes was established, in 734, shozei (the rice tax stored in provincial offices warehouse) with the mixed Kanto (rice gathered as rice field tax and stored in various provinces) was enacted, and in 736, land taxes on Koden (field administered directly by a ruler) paying to Kyoto were begun.
四子政権時代には律令財政が確立され、天平6年（734年）に官稲混合による正税が成立し、天平8年（736年）には公田地子の京進が開始された。