It is due to an interesting episode around the start of the prior century. Brazil started encouraging poor Japanese to immigrate there, promising a better life. Thousands went. Things didn't turn out as planned, with a lot of terrible racism in Brazil, crippling discrimination, and... oh, all those fun things. So Japanese stopped going there after that initial wave, but the ones already there couldn't afford to leave so they stuck around. Then around the late 90s, Japan decided they needed factory workers so they invited the decedents of those Japanese to immigrate back to Japan. Many thousands came back. So as a result, both here and Brazil has many Brazilians with Japanese blood.
Very interesting! You learn something new every day!