Shimotsuki Kouzaburou was a member of the Shimotsuki Family and a swordsmith who crafted the Great Grade Blades, Wado Ichimonji and Enma. He was born in Wano Country, but illegally departed from there 55 years ago and eventually settled down in what became Shimotsuki Village in the East Blue. There, he fathered a son named Koushirou, making him the grandfather of Koushirou’s daughter Kuina.

(Source: One Piece Wiki)