|Sage of Six Paths|
The Sage of the Six Paths (六道仙人, Rikudō Sennin) was the legendary figure who founded the arts of ninjutsu and created the ninja world. He defeated the Ten-Tails and sealed it within his own body, thus becoming the first jinchūriki.
According to Jiraiya, the Sage was a monk who appeared long ago in an age of endless war. He was the first to discover the truth of chakra, and with it he tried to lead the world to an era of peace instead of conflict. He travelled across the land, spreading his ideal and religion, the Shinobi Sect (忍宗, Ninshū), which eventually came to be known as ninjutsu. His great deeds and ultimate desire to bring peace to the war-torn world made him widely known as the Saviour of this World (この世の救世主, Kono Yo no Kyūseishu). Centuries ago, the sage defeated the most powerful demon in the ninja world, the Ten-Tails, and was praised as a god for the virtue of his victory. In order to protect the world from the Ten-Tails, the Sage developed a certain technique to seal the beast within his own body, giving him the ability to harness and control its overwhelming power; he became the first jinchūriki. However, this offered only a temporary solution. In the event of his death, the seal would break and the Ten-Tails would once again be unleashed upon the world. Aware of his impending fate, the Sage used Creation of All Things (万物創造, Banbutsu Sōzō) to divide the Ten-Tails' chakra into nine individual constructs that would become known as the tailed beasts. As a final precaution, he used Chibaku Tensei to entomb the physical remains of the Ten-Tails body within a gigantic stone prison, which he hurled into the heavens, creating the moon. It is later revealed that the Sage gave names to these beasts. The Sage would leave behind a tablet for his descendants, detailing the history of his struggle with the beast. Only those who possess the Rinnegan can fully decipher the contents of the tablet, while a reader with a lesser dōjutsu can still partially interpret the information. Some time after creating the tailed beasts, the Sage told them that they would be together even when separated, and that one day they would again be a single entity.
The Sage's ultimate wish was to establish peace across the world, but it was a goal that would never be achieved in a single lifetime. Knowing this, he chose to entrust his strength, dream and legacy to his two sons. The older son, who inherited the Sage's "eyes" (his powerful chakra and spiritual energy), believed that power was the true key to peace. The younger son, who inherited the Sage's "body" (his powerful will and physical energy), believed that love was the true key to peace. On his deathbed, the Sage chose his younger son to be his successor. Overcome by bitterness and envy, the older son attacked the younger, beginning a war between them. Their feud would continue on through their descendants: the Senju clan and the Uchiha clan.
The Sage of the Six Paths was a man who sought peace by spreading his wisdom across the world. He was exceptionally wise, as he was able to bring about a great change to the world by simply disseminating the principles of chakra and his religion. He also seemed to care a great deal for the tailed beasts when they were still with him; he gave them each a name as a sign of their individuality, and told them that no matter how far apart they grew, they would always be together, and would someday be led down the right path. In return, the tailed beasts showed respect and adoration for the Sage. Kurama even shed a tear at the thought of his imminent passing, suggesting that the beasts might even have viewed him as a sort of father-figure.
Although initially depicted as a silhouette, several details about the Sage's appearance can be inferred. He had a small goatee and short light-coloured hair that spiked up in the front with two distinctive pieces of hair resembling horns. He wore a full-length cloak (haori) with a high collar, revealing his necklace with six red magatama. These symbols were later mimicked by Nagato's Deva Path, and the seal around the neck of Naruto Uzumaki's Nine-Tails Chakra Mode and Tailed Beast Mode. On the back of his cloak was a stylised Rinnegan with nine magatama in three rows beneath it. In one appearance where his face was partially visible, he was in an elderly state.