personal grudge

Kyūjitai form of 私鉄 (“private railway”)

a street corner / a city street

Inner Mongolia (an autonomous region of China)

Outer Mongolia

the Paleogene period

Obsolete spelling of シカゴ (Shikago, “Chicago (a city in Illinois, United States)”)

"Historical kana usage", a prescriptive method of using kana to write Japanese. Devised in the Edo period by Keichū (契沖) and taught in schools until 1946, it aims to be etymologically faithful and reflects earlier stages of the language (Heian period and earlier).

revisionism

I don't speak Japanese