This term started because the war was considered as a fight between Kiyomori and Munemori of the Taira family and Yoritomo, Yoshitsune, Yoshinaka of the Minamoto clan due to the fact that the war started with Prince Mochihito's call for "destroying the Taira clan," the transition from the Taira clan government to Yoritomo government (Kamkura bakufu), and the effect of stories such as "Heike Monogatari" (The Tales of the Heike) and "Genpei Seisuiki" (The Rise and Fall of the Genji and the Heike) had on the people.
この争乱が以仁王の「平氏追討」の令旨に始まること、平氏政権から頼朝政権（鎌倉幕府）に交代したこと、民間レベルでは『平家物語』や『源平盛衰記』などの影響から清盛・宗盛ら平氏一門と頼朝・義経・義仲ら源氏一門の争いと受け取られてきたことなどが、この呼称を生んだといえる。