Minamoto no Yoshitsune was well-known as hero at the age of 22. History wrote that time the war between Genji and Heike started again. Those 2 families have become enemy since a long time ago.
Surprisingly, Yoshitsune was raised by Kiyomori (the head of Taira Clan, Heike). He was in love with Yoshitsune mother who was told to be the most beautiful woman at that era. But, soon Hideyori felt afraid of Yoshitsune’s potency and sent him to be a monk.
Yoshitsune started living as Budha’s servant, but he also trained himself. When he was 16, he got out of the temple with great warrior skills. He, then join his brother (from different mother), Minamoto no Yoritomo in Kamakura. Together, they build the strength to avenge their father, Minamoto no Yoshitomo.
However the manga is quite fascinating. The plot takes place in the same era as many historical evidence written. But, the mangaka put special spices in characterization. Yoshitsune here was not really the heir of Genji, but he was just a street performer who really looks like Ushiwakamaru (Yoshitsune’s child name). The real Ushiwakamaru suffers chronic disease, and soon will die. So, his parent asks that street performer,Hyota, to replace his place.
You can find it online in dragonvoice