This loss of power was due to opening of Japan to European trade. Traders brought new weapons, in particular guns. The new weapons were more effective than the samurai and their sword as anyone could use them. Merchants gained status and became a part of the Japanese hierarchy.
This started may 5th 1864 to may 7th 1864. during this battle more people were wounded um it doesn't really say what the point was but go to google and it gives you the time line