His father: Tsunamasa OYAMA (the second son of Takamitsu SAIGO, a feudal retainer of the Satsuma clan, adopted by Tsunatake OYAMA, a feudal retainer of the Satsuma clan, an expert of gunnery)
父大山綱昌（薩摩藩士西郷隆充の次男、薩摩藩士大山綱毅の養子。砲術専門家）