Sakai Hisatsune served as a bushō during the Sengoku period. He was a retainer of Oda Nobunaga. His common name was Kyūzō. Hisatsune as his real name cannot be confirmed from authenticated sources.
In 1555, Hisatsune was born as the eldest son of Sakai Masahisa, a retainer of Oda Nobunaga. Hisatsune also served under Nobunaga. The origins of the Sakai clan are uncertain, and were either Mino Province or Owari Province.
In 1568, Hisatsune joined in Nobunaga’s march upon the capital to Kyōto to install Ashikaga Yoshiaki as the fifteenth shōgun of the Muromachi bakufu. Hisatsune participated in the Siege of Kannonji Castle defended by Rokkaku Yoshikata and received a commendation from Yoshiaki for his contributions.
Thereafter, he joined several of the primary conflicts entered into by Nobunaga. On 6/28 of Genki 1 (1570), at the Battle of Anegawa, Hisatsune was killed in action by the forces of Azai Nagamasa. He was sixteen years old.