The Battle of Ichi-no-Tani was fought between the Minamoto and Taira clans on 20 March 1184 during the Genpei War.
Minamoto Yoshinaka's death left his clan free to concentrate on their struggle with the Taira, whose leaders had retreated to the fortress of Ichinotani. Led by Minamoto Yoshitsune, an army advanced down the coast toward the fort. Yoshitsune positioned his main army facing the Taira defensive line. The battle opened in traditionally ritualistic fashion: Minamoto samurai approached the Taira line, shouting out their lineage and military record, waiting for a Taira warrior to propose single combat. As this prelude to full battle was played out, Yoshitsune led a mounte ddetachment to the rear of hte fortress, where it backed on to a steep cliff. The Taira had neglected their defenses on this side. But Yoshitsune's forces rode down the cliff and stormed into the rear of the Taira position. The Taira staged a fighting retreat to their boats on the beach. One account of the battel tells how the Minamoto samurai Kumagai Naozane, grieving for his 16-year-old son killed earlier in the battle, found himself in a position to kill the 16-year-old Taira Atsumori - which he did, after much soul-searching. Most of the Taira escaped by sea, but the Minamoto pursued them along the coast. Yoshitsune drove the Taira out of their last stronghold at Yashima. Dispirited, the Taira fell back to the shore of the Shimonoseki Strait. There Yoshitsune found them in April 1185 for the decisive Battle of Dan-no-ura.