During the Jinshin War of 672, Ato took side of Oama no Miko (Prince Oama, who later became Emperor Tenmu), and became a messenger to mobilize troops from the Tokaido region.
672年の壬申の乱で大海人皇子（天武天皇）に従い、東海道に軍の動員を命じる使者になった。