Shin'okoku (秦王国) is the name of a country or location that appears in the book of Sui as being in the region of Wa.
The Shin'okoku (秦王国) appears in the book of Sui in "Ring 46 Japanese missions to Sui China brought by Japanese envoys to the Sui dynasty (俀国) sent by king Tarishihiko [ja] to Emperor Yang of Sui.
Mainly in the western part of the Chugoku region.
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