Hashirama Senju

, the, was the founder of Konoha, the older brother of Tobirama Senju (the Second Hokage), and the grandfather of Tsunade (the Fifth Hokage) and Nawaki.

Background
Hashirama was originally the leader of the Senju clan. Under his leadership the Senju clan came to be regarded as one of the two most powerful clans in the world, rivaling the Uchiha clan. Because of this, when someone hired the Senju clan, the opposing side would hire the Uchiha clan and vice-versa, causing frequent battles between the two. Eventually growing tired of the constant fighting, Hashirama and his clan approached the Uchiha and offered a truce with them. Allied with Madara and his clan, the two groups founded Konohagakure.

When deciding who should become the leader of Konoha, the villagers selected Hashirama over Madara for the title of First Hokage. Fearing that Hashirama would oppress the Uchiha, Madara left the village, and challenged Hashirama's rule. In the aftermath of their battle, Madara was believed to have been killed, and the Valley of the End was created. To commemorate the battle, two statues, of Madara and Hashirama, were carved into the earth surrounding the valley.

During his time as Hokage, Hashirama came into possession of a scroll filled with kinjutsu, which he sealed away in order to keep the jutsu within a secret. He also defeated Kakuzu, who had been sent to assassinate him by Takigakure. At some point, Hashirama gained control of several tailed beasts. He spread these beasts to other, newly-formed villages in an attempt to maintain peace and equalize the powers between the nations, but it did not stop the outbreak of the First Great Shinobi World War. Thinking about the future of Konoha, he and his younger brother, Tobirama Senju, trained the young Hiruzen Sarutobi. Hashirama would eventually die during the war, but not before passing on the title of Hokage to Tobirama.

Sometime after Hashirama's death, Orochimaru experimented with Hashirama's DNA. Desiring Hashirama's unique abilities, Orochimaru exhumed the Hokage's body and infused sixty child test subjects with his DNA, hoping that one would prove able to use Wood Release. Only Yamato survived the process. Danzō Shimura's right arm has also been infused with Hashirama's DNA through a similar experiment with Orochimaru, in the hopes of controlling the powers of the Nine-Tailed Demon Fox, as well as to increase his physical energy to maintain the ten Sharingan embedded on his right arm.

Personality
Hashirama was shown to be a very calm and collected person, as well as kind and caring, with a deep sense of loyalty. He saw the people of Konoha as a part of his own family, and his legacy took a firm root in the village. He was also shown to be a very wise and insightful man, as he passed on great teachings to Hiruzen. It was he who first believed that all Leaf ninja should show a true loyalty to each other, and that a Kage must be willing to put his life on the line for his village to set an example for all others. This belief of his is known as the Will of Fire.

Abilities
Hashirama Senju was considered by both Madara Uchiha and several Konoha Jōnin as the most powerful ninja of his time. He was greatly respected by every shinobi during his life, such that Madara claimed Hashirama was the one person whom he respected the most as well as detested. He knew how to perform a great number of jutsu, and was otherwise knowledgeable of those he could not, as indicated by creating the Scroll of Seals and his familiarity with Summoning: Impure World Resurrection.

His prowess and abilities were so great that he was able to not only fight on equal footing with Madara despite the power of his Eternal Mangekyō Sharingan and having the Nine-Tailed Demon Fox at his side, but also survive the battle and gain victory in the end. The injuries which he caused to Madara were so great that even now they still affect him tremendously.

Wood Release
He was most famous for his Wood Release jutsu, a Kekkei Genkai to mix earth- and water-natured chakra to create this new element. By converting chakra into the source of life, he was able to create trees, cause them to grow to great sizes and manipulate them to diverse shapes and battle uses at will. It was said that this ability was used to create the very landscape and foundation that Konoha is built on. This ability was apparently unique for him, since none of his relatives were shown using the ability. Even Yamato, the only person to have proved compatible with Hashirama's genes, found his use of Wood Release to be much weaker in raw power. Yamato has also shown great skill in standard water and earth techniques, so it is presumed Hashirama could do water and earth techniques as well.

The ability Orochimaru most highly praised him for was his unique ability to control tailed beasts. Of all his considerable talents, it was this ability in particular that made Hashirama unparalleled in the shinobi world. At one time, he had many of the beasts in his possession. This ability was greatly amplified by his crystal necklace, which Yamato suggested was a requirement to control even Naruto's partial lapses into tailed forms.

Invasion of Konoha arc
Both he and Tobirama were revived from the dead by Orochimaru using Impure World Resurrection to fight Hiruzen during the invasion. While fully aware of what was going on, and saddened that he would have to fight his former student, Hashirama and his brother were robbed of their free will as a result of a seal employed by Orochimaru into the backs of their heads. Hiruzen quickly resolved to kill his masters and used a very powerful fire technique that was easily countered by one of Tobirama's walls of water that was then turned into an attack that was stopped by Hiruzen's own earth wall.

During the battle, he demonstrated great teamwork and combination attacks with his brother. He also demonstrated his great Wood Release abilities, forcing Hiruzen to summon Enma for assistance, and at the same time showed great taijutsu skills. His soul along with his brother's were eventually sealed by Hiruzen when he combined the Dead Demon Consuming Seal and the Shadow Clone Technique to strike both of them at the same time. Before his soul was completely removed, he and his brother apologized to their former student for the trouble they had caused.

Trivia

 * His face on The Hokage Monument has a crack across the bridge of the nose like Iruka Umino.
 * The necklace, worn by Tsunade and later worn by Naruto, originally belonged to Hashirama.
 * In the English dub version of the anime, his Wood Release was called "Secret Earth Jutsu" rather than "Wood Style."
 * Hashirama, along with Tobirama, Minato, and the Konoha symbol, had his face appear in the ending omake of Shippūden episode 129 within the fireworks.
 * Hashirama is one of only four people said to be able to truly control a tailed beast, the others being Madara Uchiha, Yagura, and Killer Bee.
 * According to the third Naruto databook:
 * His hobbies were bonsai and sculpture.
 * His favorite opponent was Madara Uchiha.
 * His favorite food was mushroom mixed soup.
 * His favorite quote was.

Quotes

 * "The fellow countrymen of the leaf make up each part of my body ... those of the village believe in me, and I believe in them. That's what it means to be Hokage!"
 * "Whenever you live, there will always be war."
 * "Those who stray from the path of justice have no courage, but under the wing of a strong leader, cowardice cannot survive."