Uchiha Clan

The was one of the four noble clans of Konohagakure, and was also reputed to be the village's most powerful clan, producing shinobi that were exceptionally talented and battle-oriented, and in possession of the renowned Sharingan. Together with the Senju clan, they founded Konohagakure, but is now almost extinct after its downfall.

Founding
The Uchiha clan descended from Indra Ōtsutsuki, the elder of the two sons of the Sage of the Six Paths. Indra inherited the Sage's "eyes", powerful chakra and spiritual energy. When it came time for the Sage to choose a successor, he questioned the two on what course of action they would follow to bring order to the world. Indra believed that power was the way to bring peace, while Asura Ōtsutsuki, the younger son, believed love was the way. The Sage favoured Asura's ideal, and therefore designated him as his successor, causing Indra to be filled with jealousy and hatred. From this hate came what Tobi calls the. From Asura descended the Senju clan who would be the eternal rivals of the Uchiha. However, the Uchiha suffered another more dangerous curse: a passionate love that can become a bottomless well of despair the moment someone they care for dies.

Before the founding of the ninja villages, the Uchiha were one of the many mercenary clans for hire. Because of their Sharingan as well as battle prowess, the Uchiha clan came to be known as one of the two strongest clans, the other being the Senju clan. Madara Uchiha was particularly powerful, and, upon attaining the Mangekyō Sharingan, took control of the clan. Under his leadership the Uchiha grew stronger, conquering whatever clans they came upon, such that, whenever the Uchiha clan was hired for a job, the opposing side would hire the Senju, and vice versa.

Konohagakure
Some time before Konoha's founding, some members of the Uchiha clan began to willingly surrender, realising that they were outclassed by the Senju. The Senju later grew tired of the endless fighting, and approached the Uchiha clan with a peace treaty once again. Though rejected time and time before as Madara feared that an alliance would destroy the Uchiha clan, he willingly accepted after witnessing Hashirama's resolve. The two clans came together to form Konoha, with Hashirama Senju, leader of the Senju clan, being selected as Hokage. Madara believed that this was proof that the Uchiha would be made subservient to the Senju, but his clan saw this only as his attempt to rekindle the flames of war. They turned their backs on him, and he defected.

Following Madara's betrayal, having gone into hiding after faking his death in the battle against Hashirama, the Second Hokage Tobirama Senju gave the Uchiha control of the Konoha Military Police Force as a sign of trust. However, this was really just a way of keeping the Uchiha's emotions in check so the village would not end up with another Madara. Over the years, some Uchiha, such as Setsuna Uchiha, came to realise their ostracism and believed that they were being purposely kept out of Konoha's governing affairs. Though Setsuna and his followers tried to rebel against the village as Madara did, they found that it was too late to make a difference, as the Senju had already completely suppressed the Uchiha. Despite Tobirama's attempts, it only caused a greater rift between the Uchiha and the village. The matter grew worse when a young Obito Uchiha, presumed dead at the time, witnessed the death of Rin Nohara, his team-mate and a girl Obito loved at the hands of Obito's rival, Kakashi Hatake. In the aftermath, Obito became a follower of Madara's ideals, vowing to create a world where he and Rin could be together again.

Downfall
Years later, after the Nine-Tails' Attack on Konoha, Konoha's elders began to suspect that an Uchiha was behind the attack because of their ability to control the Nine-Tails with their Sharingan. Tobi stated that the clan was forced to live in a corner of the village, ostracised from the rest of the community, and placed under heavy surveillance, though only the latter has collaborating evidence. This gave birth to ill-will amongst the clan and the Uchiha interpreted this as confirmation of what Madara had warned them of years earlier, and began to plan overthrowing the village. Itachi disagreed with his father's coup d'état plan, and informed Konoha's leadership of what the Uchiha were up to. Shisui Uchiha, who had been told to keep an eye on his best friend Itachi also disagreed with the clan's plan and joined Itachi in his mission to put a stop to it. Shisui attempted to use the ability of his Mangekyō Sharingan: Kotoamatsukami to stop the coup d'etat, but was stopped by Danzō — who was determined to protect the village his own way — stole Shisui's right eye from him. Saddened by the turn of events, Shisui met with Itachi and entrusted him his left eye before the elder came after it as well, telling him to protect the village and the name of the Uchiha.

The Third Hokage, who had disagreed with the treatment the Uchiha were receiving, tried to negotiate for a more peaceful solution, but as time passed and that strategy seemed to be getting them nowhere, Danzō took matters into his own hands and inveigled Itachi to commit the genocide with threat of his clan's actions creating another war and innocent children, such as his little brother, becoming a casualty.

Survivors
Only three Uchiha survived their clan's genocide: Itachi, the clan's killer, Sasuke, Itachi's younger brother, and Obito, who, acting as Madara, assisted Itachi with the massacre.

Years later, Sasuke kills Itachi to avenge their family — the way he had intended — only to discover the details surrounding why Itachi did what he did. Saddened by his brother's sacrifice and angered by Konoha's involvement, Sasuke teams up with Obito to destroy the village. When Itachi is reincarnated during the Fourth Shinobi World War, Sasuke is able to speak with him and decides that destroying Konoha is not the solution.

Madara Uchiha is also brought back to life during the Fourth Shinobi World War through the actions of Obito. Madara is then incapacitated when his body is used to revive Kaguya Ōtsutsuki, courtesy of Black Zetsu. Obito himself dies shortly after while protecting Naruto Uzumaki and Kakashi Hatake from one of Kaguya's attacks, and when Kaguya is sealed by Naruto and Sasuke, Madara perishes moments later as the tailed beasts were extracted from his body, which ultimately leaves Sasuke as the sole survivor of the entire Uchiha clan.

New Era
Years later after the war, Sasuke would go to finally overcome the curse and have a daughter with Karin, therefore continuing the Uchiha bloodline, effectively beginning the restoration of his clan as he originally wanted.

Meanwhile, Shin, a former experiment of Orochimaru who was fascinated with Itachi of the Uchiha clan, would claim the Uchiha name with his clones with the desire to kill Sasuke to restore honour to the Uchiha and revive Akatsuki.

Abilities
The Uchiha were famous for their powerful chakra, exceptionally strong techniques, and natural aptitude for anything combat-related. The clan possessed an innate affinity for Fire Release nature transformation, with even the youngest of members able to use it from just observation. They have created several techniques and use this nature transformation more skilfully than any other. Their signature technique was the Fire Release: Great Fireball Technique. Clan members were not recognised as adults by the rest of the clan until they could successfully use this technique. The Uchiha were also highly known for their mastery of ninja tools. They themselves invented many shuriken move sets which required the use of thin metal wires, such as the Windmill Triple Blades technique. They were apparently also somewhat skilled in barrier ninjutsu, having created the Uchiha Flame Formation which, still holding to their natural affinity for fire, created a barrier that burned whatever came in contact with it.

The Uchiha clan were most feared for their kekkei genkai, the Sharingan. This dōjutsu gives them the ability to see the "colours" of chakra, allowing them to analyse and copy their opponent's skills, along with a number of other abilities. Due to the process necessary to awaken it, only a select few Uchiha manifested the Sharingan. Due to their natural affinity for battle, and their proficiency with genjutsu, many ninja considered it more tactically favourable to flee rather than face an Uchiha in one-on-one combat. Among the techniques granted by the Sharingan, Izanagi and Izanami are deemed to be forbidden, due to their effect of rendering the user blind in exchange for creating genjutsu capable of escaping death or trapping the opponent without failure. Various non-Uchiha have had the Sharingan implanted into them, as well.

Madara and Izuna were the first two Uchiha to awaken an advanced form of the Sharingan known as the Mangekyō Sharingan, which can be activated by experiencing a pain similar to the one needed to awaken a regular Sharingan. However, frequent use of the Mangekyō Sharingan deteriorates the user's eyesight and results in blindness. Only by taking the eyes of a close genetic match, such as a sibling, can one's vision be restored, a process that results in the creation of an. Itachi indicated that the intricacies of the Mangekyō Sharingan were only discovered after decades of trial and error, implying that many Uchiha throughout history had attempted to gain the Mangekyō Sharingan.

Madara, a reincarnation of Indra, was able to further evolve his Sharingan into the Rinnegan after he stole and integrated the DNA of Hashirama Senju, Asura's reincarnation at the time, into his body. Fusing the chakra of Indra and Asura caused the Rinnegan to awaken, restoring the Izanagi-induced blindness in his left eye. However, he noted that the dōjutsu did not manifest until he was nearing the end of his natural lifespan. After meeting Hagoromo Ōtsutsuki during a near-death experience, Sasuke awakened a unique Rinnegan containing six tomoe in his left eye.

Trivia

 * "Uchiha" is another way of pronouncing, which is the clan's symbol. Uchiwa can be used to fan flames, making the flame hotter — referring to the fact that the Uchiha is a clan of Fire Release users.
 * Attire-wise, the Uchiha have always favoured high-collared outfits with their clan's symbol proudly emblazoned on the back. Furthermore, during the Warring States Period, the Uchiha that chose to wear armour often refused to have any armour on their back to proudly display their clan's symbol. Over the generations, their attire has changed with their attire initially consisting of a dark coloured mantle along with pants, which later became simple shirts and pants, all the while retaining the high collar.
 * Prior to settling on Konohagakure, they resided in an enclave of small wooden buildings surrounded by forest.
 * Most of the powerful techniques exclusively used by the Uchiha (Tsukuyomi, Amaterasu, Susanoo, Izanagi, Izanami and Kotoamatsukami) are named after Shintō deities from the Japanese creation myth.
 * Itachi, Sasuke, and Obito are the three Uchiha that remained after the massacre, and all three eventually became missing-nin, allied with Akatsuki. All three eventually awoke their Mangekyō Sharingan.
 * In the earlier stages of the series, Kakashi stated that there are rumours the Uchiha clan's Sharingan was derived from the Hyūga clan's Byakugan. However, Kurama is the only one to know the full truth about the Uchiha clan yet appears to have no intention of revealing what it knows. It is later revealed that the Uchiha and Hyūga have a common ancestor in Kaguya Ōtsutsuki, who used both the Byakugan and Rinne Sharingan, a Rinnegan with Sharingan characteristics.
 * According to Obito, the Uchiha clan is destined to a life of revenge against their hated enemies, the Senju clan and Konohagakure. However there are exceptions in the form of Itachi, Shisui, Naori and Kagami Uchiha and later Sasuke, who had opposing ideals.
 * The clan had various places affiliated with them:
 * A senbei shop that was famous throughout the village.
 * A shrine as well as a secret meeting place under said shrine.
 * A river which runs through their compound.
 * A supply base in Sora-ku that Hebi visited for supplies.
 * A hideout that served as the arena for the final battle between Sasuke and Itachi.