There are various opinions about the actual reason of the death of MINAMOTO no Yoritomo, however, according to this book, it was because he saw a ghost of MINAMOTO no Yoshitsune at Yamatogahara (the present Tsujido and wide area of Chigasaki) on his way back from Buddhist ceremony for bridging Sagami-gawa River, and also saw a ghost of Emperor Antoku on the sea of Inamuragasaki, then he fainted and was struck down by a illness at Kamakura.
源頼朝の死について、建久10年（1199年）に、相模川橋供養の帰路、八的ヶ原（現在の辻堂および茅ヶ崎の広域名）で源義経らの亡霊を、稲村ヶ崎海上に安徳天皇の亡霊を見て、鎌倉で気を失い病に倒れたと記しているが、実際の死因については諸説ある。