Looking back the political situation around 757, Emperor Shomu, who had reigned over the central government until then, died in 756, and multiple powerful groups inside the government started to fight to take the leadership of the government.
757年当時の政治状況を見ると、それまで中央政府に君臨していた聖武天皇が756年に没し、政府内で複数の勢力が主導権争いを始めていた。