If such chronological order was determined from the very start of compiling "Chronicles of Japan," it can be estimated that the first year of Emperor Tenmu was designated for the next year of Jinshin not because it was the year of enthronement but because the Jinshin year was under the reign of another emperor.
もし、最初の段階での『日本書紀』が天武元年を壬申年の翌年においていたのなら、それは即位年にあわせたからではなく、壬申年が別の天皇の年だったからだと推定できるのである。