When his elder brother MINAMOTO no Yoritomo rose up in arms to defeat the Taira clan (Jisho-Juei War), he joined his brother, and after such battles as the Battle of Ichinotani, the Battle of Yashima, and the Battle of Dannoura, he destroyed the Taira clan as the most distinguished contributor to the victory.
兄源頼朝が平氏打倒の兵を挙げる（治承・寿永の乱）とそれに馳せ参じ、一ノ谷の戦い、屋島の戦い、壇ノ浦の戦いの合戦を経て平氏を滅ぼし、その最大の功労者となった。