武田氏
At an early age, Nobuyuki's father served under the "daimyō" Takeda Shingen and sent Nobuyuki as a hostage to prove the Sanada clan's loyalty to the Takeda clan. After the Takeda clan was destroyed by Oda and Tokugawa army, Nobuyuki fled to Ueda Castle, the stronghold of the Sanada Clan and where his family were.