The Taika reforms were not a single-day change

A coup is not a completed administrative reform

The Isshi Incident of 645 removed Soga no Iruka and changed political leadership. It did not complete land administration, population registration and revenue collection on that day. Separating the coup from the wider reform reveals subsequent institutional work.

The later-compiled Nihon Shoki records an edict in 646, with possible projection of subsequent institutions. A stated programme differs from evidence of its complete application. Officials, records and communications were necessary between policy and practice.

Connecting people, land and obligations

Population registers helped define land allocations and obligations through residence, age and status. The Kōgo register of 670 marks that work. Central administration required information about distant communities in usable form.

Provincial officials sent from the centre differed from district officials drawn from local influential families. New offices incorporated existing relationships. Records, stores and communications needed people and facilities to make rules work.

Institutional development towards 701

The Taihō Code of 701 established administrative and penal arrangements decades after 645. Rules provided continuing standards across changes of personnel. The coup and the code therefore represent different dimensions of state formation.

Classification connected land use with taxes and labour obligations. A palace-only account misses villages and offices. The sequence of coup, programme, registers and code traces political change into everyday administration.

Before and after

1. 645

   Soga no Iruka is killed in the Isshi Incident.

2. 646

   The chronicle records the reform edict.

3. 670

   The Kōgo population register is compiled.

4. 701

   The Taihō Code is established.

Key terms

Isshi Incident

The coup killing Soga no Iruka in 645.

Population register

Household records supporting taxation and administration.

Penal and administrative codes

A legal system defining penal and administrative rules.

What supports the account?

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