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eastern country; eastern provinces; Kanto provinces
東国の武士が勢力を拡大した。
Warriors from eastern Japan expanded their power.
平安時代、東国は西国とは文化が異なった。
During the Heian period, eastern Japan differed culturally from western Japan.
鎌倉幕府の成立により、東国の武家政権が確立した。
With the establishment of the Kamakura shogunate, a samurai government took hold in eastern Japan.