barbarians to the east and west
Historical term from the perspective of ancient China, referring to non-Chinese peoples on the eastern and western borders. Used as a yojijukugo.
"Tōi Seijū" is a term that referred to surrounding non-Chinese peoples in ancient China.
From Chinese 東夷西戎 (dōngyí xīróng), literally 'eastern barbarians and western barbarians'. The exact historical derivation is uncertain; the spelling is conventionally associated with this meaning.