Senju Clan

The was a group of shinobi that was considered to be one of the strongest clans in the ninja world during the war-torn era before the founding of the hidden villages. Together with their rivals and distant relatives by ancestor, the Uchiha clan, they are responsible for founding the first hidden village named Konohagakure and making the village into what it is today. They are also noted to be distant relatives of the Uzumaki clan.

History
The Senju clan descended from the younger of the two sons of the Sage of the Six Paths who was born with the "body" of the Sage, inheriting his father's strength of will and physical energy and believed that love was the key to bringing peace to the world. The Sage grew to favour the ideals of his younger son over those of his older son, who believed that power alone was the true key to finding peace. Therefore, on his deathbed it was the younger of the two brothers that the Sage chose to name as his successor. The elder brother, bitter and hateful at having being denied what he felt was rightfully his to inherit, attacked his younger sibling. The Uchiha clan would descend from the elder brother, resulting in the bitter centuries-long rivalry between the Senju and the Uchiha.

The Senju clan gained their fame in the era before the founding of the hidden villages. Where other clans focused on mastering one particular skill, the Senju were prodigious in all skills, from ninjutsu, to taijutsu, to genjutsu. Because of this, they were as, which gave them their name.

The most famous member of the clan was their leader, Hashirama Senju. His unique Wood Release ninjutsu even gave the clan the nickname the. This Wood Release, and his ability to control the tailed beasts, made him the greatest shinobi of his time.

The Senju's place at the top of the shinobi world was undisputed, but there was one clan that was able to stand up to them: the Uchiha clan. Whenever one country hired the Senju, their enemies would hire the Uchiha, and vice versa. This led to a rivalry between the two clans and, more specifically, between the leaders of the clans, Hashirama Senju and Madara Uchiha.

However, in a world of constant bloodshed, Hashirama had a dream of peace, and a great love for his fellow men. Known as the, this belief made the Senju clan propose a truce to the Uchiha clan. Weary of fighting, and persuaded by Hashirama's great charisma and negotiation skill, the Uchiha accepted, ending their bloody rivalry. Only Madara was against this truce, believing the Senju would one day destroy the Uchiha clan. He was forced to accept, but his humiliation wouldn't end there.

Some time after the alliance between the Senju and the Uchiha was signed, the Land of Fire hired them to stabilise its borders, and the clans created a permanent settlement within the country. Thus, Konohagakure was founded, and, with it, the system of one Hidden Village per country. As the system spread throughout the world, the constant violence stopped, and Hashirama's dream began to become a reality. But it would soon start again after Hashirama was elected as the First Hokage; a move Madara felt was a humiliation and made him decide to leave the new village, eventually returning to attack it.

Throughout the years, the Senju retained their supremacy over Konoha, and made the village into what it is today. After the First Hokage's death, his younger brother, Tobirama Senju, stepped up to become the Second Hokage. Although likely not a Senju by blood, Hiruzen Sarutobi, who would become the Third Hokage after the Second's death, was trained by both the First and Second. His successor, Minato Namikaze, was the student of Jiraiya, who was a student of the Third. Tsunade, the Fifth Hokage, was not only a student of the Third, but also the granddaughter of the First and the grandniece of the Second. All of them strongly held to the Will of Fire philosophy.

It is unknown if the Senju clan still exists as an independent clan since there are no known persons with the Senju name alive — with the Fifth Hokage, Tsunade, being the only possible exception to date. It is very possible that the Senju clan disbanded into smaller clans and families, especially since they never had specific traits or techniques like the Uchiha or Hyūga clans with which to easily identify them. Their legacy however, lives on strongly in the hearts of the people of Konoha.

Trivia

 * Madara Uchiha was able to awaken the Rinnegan after integrating Senju DNA into his body. This dōjutsu, however, did not awaken until he was nearing the end of his natural lifespan.