神武以来じんむこのかた

noun which may take the genitive case particle 'no', adverb

since the era of Emperor Jimmu; unprecedented in Japanese history

Used to emphasize that something is the first of its kind in Japan's recorded history, often in formal or journalistic contexts. The phrase is fixed and not used as a general adverb.

• これは神じん武む以来このかたの大だい改かい革かくだ。

  This is the greatest reform since the era of Emperor Jimmu.

• 神じん武む以来このかたの快かい挙きょと称たたえられた。

  It was praised as an unprecedented achievement in Japanese history.