Rurouni Kenshin OVA - Kenshin (18)
Kenshin had promised Katsura Kogo that he would continue fighting on the side of the imperialists against the Shogunate, until the "new age" was achieved. Here he looks over the carnage at the Battle of Toba-Fushimi, a real historical battle in which the Choshu, Satsuma and Tosa loyalists combined forces to defeat the Shogun's army, led in part by the Shinsengumi special forces.
At last, Kenshin thinks, he's done with the life of the sword. It is at this moment that he takes up his vow to never kill again. A few moments later he receives the
sakabato that becomes his weapon for most of the rest of his life.