Its inscription is the important source of the ancient diplomatic relations between China and Japan and its domestic politics.
In the Chinese historical book Records of Wei, which is part of the Records of the Three Kingdoms, Wa (Japan) had a large civil war in the period.
[2] It is assumed that the sword was bestowed by Emperor Ling on a king of Wa, though its detail is not yet unknown.
Then the sword was passed to a local ruling family in the region, who constructed the Tōdaijiyama Kofun in the late 4th century.
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