織田信秀
Depending upon the source, Oda Nobunaga and the entire Oda clan are descendants of either the Fujiwara clan or the Taira clan (specifically, Taira no Shigemori's branch). His lineage can be directly traced to his great-great-grandfather, Oda Hisanaga, who was followed by Oda Toshisada, Oda Nobusada, Oda Nobuhide, and Nobunaga himself.