Ansei era

time for doing something / period of time / season

important, significant

importance, consequence, significance

age, era, period (of time) / the times, spirit of the age / antiquity / a time in one's life, one's days (in college etc.)

history / the study of history

Japan

(archaic) Japan

Short for 日本国 (Nihon-koku): Japan (a country and archipelago in East Asia) / a surname

for a while, for a period of time