(historical) the Central African Empire

historic, historical / already-happened, past / former, old, traditional

Central Africa / Short for 中央アフリカ共和国 (Chūō Afurika Kyōwakoku, “Central African Republic”).

the Central African Republic

important, significant

importance, consequence, significance

history / the study of history

a land, a large place / a country in general, a region / a country as in a nation, a state / the office of emperor, the crown; affairs of state / a province of ancient Japan

"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).

as far as ... is concerned; in terms of ...