The Goseki's Daisho was granted by the Emperor to Matsu Goseki upon the founding of his family, the Goseki family. The Goseki family was destroyed by Tsume Retsu when he seized Toshi Ranbo, the family's stronghold. The blades were in hands of Goseki Mochiko, who escaped the battle with her own young son and a young girl as well, the sole surviving member of the Goseki family. They sold the blades to a corrupt Shinjo caravan master for enough koku to live comfortably for the rest of their lives. The blades never made it to the Unicorn lands, as the caravan was attacked and the blades were taken by bandits operating from the Spine of the World Mountains.