The Meiji Restoration. It was somewhat of a result of the Japanese being contacted by the outside world and realizing that they were behind.
Also the "floating world" period up to that point, so it seems like life was at least decent for people before the outside influence.
> Contact with the outside world?
Perry (US) sailed a fleet into Tokyo Bay and threatened to destroy the city if the samurai government didn’t open trade with the US (1850s).
Fearing domination by western powers (cf. China) the Japanese reformed their society and economy based on western empires (1868) and within 40 years was able to soundly defeat Russia in a war (1905).
What ended the era you describe? Contact with the outside world? I've also thought for a long time that space migration is the only real hope for the human race to avoid permanent stagnation and eventual decline.