A number of war fans were used in
Japanese feudal warfare, of varying size and material, for different purposes. One of the most significant, and perhaps most interesting, uses was as a signalling device. Signalling fans came in three varieties: a tasseled
pom-pon, a solid iron fan, or a wood and paper one, very similar to the
gunbai used today by
sumo referees. The commander would raise or lower his fan and point in different ways to issue commands to the soldiers, which would then be passed on by other forms of
visible and audible signalling. The art of fighting with war fans is
tessenjutsu.
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