This sword mounting was made for naginata (halberd) owned by Bekki Dousetsu, the founder of the Tachibana family. The halberd was made by a swordsmith, Taira-no-Iemori, before the Momoyama period (1568- 1615) while this mounting was made during the Momoyama period. Out of all the existing mountings for Japanese halberds, this is one of the oldest ones and important example to trace the history of sword mountings for halberds.
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