They are a pair of brothers and performers of the traditional Japanese music style of Tsugaru-jamisen which originated in northern Japan. They debuted in 1999 in Japan as a duo playing the shamisen. Their first album sold over 100,000 copies and made them minor celebrities in Japan, a fact that surprised the Yoshida Brothers themselves.  They have since attracted an international audience.
Their music has been a fusion of the rapid and percussive Tsugaru-jamisen style along with Western and other regional musical influences. In addition to performing songs that are only on the shamisen, they also use modern instruments such as drums and synthesizers.
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