He is the father of all shinobi, the first to bear the Rinnegan, and the first jinchurikii host. On his deathbed he had a choice, he had to choose a successor. Between his younger son(who had been born w/ his father's body granting his physical energy and stamina)or his older son(who had been born w/ his father's eyes granting him huge chakra and mental energy). He chose the younger brother, the older brother got jealous and declared war on his younger bro. The descendant of the older brother became known as the Uchiha, And the descendants of the younger brother became known as the the Senju.
if no one knows he is the sage of six paths i think im still a little blurry on the sage of paths notion anywayz i think hes the guy who made the uchihas and hosiramas
