Minamoto no Yoriyoshi and his son Yoshiie had come to the Abe clan's northern province of Mutsu to restore power over the province to the Governor; Abe no Yoritoki, Sadato's father, had been acting beyond his station.
As a result, the two clans have fought for roughly nine years, with some truces, over the course of the past eleven years, in the conflict known as the Zenkunen War, (later known in English as the Former Nine Years’ War).
Yoritoki had been killed in 1057, and so Sadato had become head of the Abe clan and head of the military effort against the Minamoto.
He had fought them in the battle of Kawasaki, in a snowstorm, defeated them and pursued them through the blizzard for a short time.
Other battles have followed, during which Sadato's attacks, along with the harsh weather and terrain, have weakened his enemies.
The Minamoto clan, supported by the Japanese government, has recovered from the disaster at Kawasaki to resume the war, returning to face Abe Sadato with a fresh army and ten thousand additional men from the Kiyohara clan in nearby Dewa province.
The second Abe son soon surrenders to the Minamotos and is exiled, but Sadato fights on.
Abe Sadato, defeated in two battles, makes a stand at his base in Kuriyagawa in 1062.
Minamoto no Yoriyoshi, along with his son, leads an assault.
They divert the water supply, storm the earthworks and stockade, and set the fortress aflame.
After two days of fighting, Sadato surrenders.
The Minamoto will return to Kyoto the following year, carrying Sadato’s head to the emperor.
