I found some info related to what appear to be early use of shields by Samurai at My Armory. I am trying to get verification and more information if I can.

It is an image of a Samurai shield from the Heian period (794 to 1185). Here is an illustration of Emperor Jinmu accompanied with a foot soldier carrying a shield.

http://horse.shrine.net/samurai/jinmu.html

It was stated that the Japanese kept the "tate", a type of pavise, and it seems the "kabuto"or the "jingasa" (equivalent of a kettle hat) would be used as a buckler when one was left with a short sword or dagger. It was also mentioned that Yagyu Shingan Ryu still practices those techniques.

Here are some photos of renactors carrying those shields:

http://www.pbase.com/joanseeuw/image/41052063
http://www.pbase.com/joanseeuw/image/41052065

It would be great if anyone can add to this info.
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