Title: Jibu Shousuke (治部少輔)

Historically: Master of Yasuda Castle. The Yasuda family had served the Nagao Clan from the time of Nagao Tamekage (late 1400s). Nagahide supported Nagao Kagetora (Uesugi Kenshin) in the coup d'etat against Nagao Harukage, so was a close aide of Kenshin from early on. He fought in many of Kenshin's wars against Takeda Shingen, Oda Nobunaga, and Houjou Ujiyasu.

He received a commendation for bravery at the 4th battle of Kawanakajima along with six other commanders, including Irobe Katsunaga.

He supported Uesugi Kagekatsu in the Otate no Ran after Kenshin's death. He died in 1582 of illness in the midst of Shibata Shigeie's rebellion. (Other accounts mention 1585, 1592.)

Though he shared the same family name as Yasuda Kagemoto and Yasuda Akimoto, also vassals of the Uesugi Clan, he was descended from a different family.

In Mirage of Blaze: he was summoned by Uesugi Kenshin to become one of the Yasha-shuu and is second in power only to Uesugi Kagetora.