Sadamasa's foster father, Zenshichiro Iesada YABE served Nobunaga ODA as his kinju (attendant), and was called ODA ke bugyo goninsyu (five administrators of the ODA family) together with Nagayori SUGAYA, Hidekazu HASEGAWA, Hidekatsu FUKUTOMI, and Hidemasa HORI.
養父の矢部善七郎家定は、菅屋長頼、長谷川秀一、福富秀勝、堀秀政と織田家奉行五人衆として織田信長の近習として仕えていた。