Madara Uchiha

Madara Uchiha is the founder of the Uchiha clan and one of the founding fathers of Konohagakure. Though he was presumably dead for decades, he is surprisingly still alive and resides within Akatsuki under the alias Tobi.

Background

When he was an adolescent, he often sparred with his younger brother Izuna, who he treated as a rival as much as he did a sibling. Eventually, both he and his brother became the first of his clan to obtain the Mangekyō Sharingan. Such a feat would bring both of them to the highest status in the Uchiha Clan, and Madara became its leader since he was the elder brother. After unlocking the Mangekyou Sharingan, Madara began to realize his descent into darkness with extended use of the Mangekyō Sharingan. After frantically trying to cure his blindness but with no avail, he finally resulted to replacing his eyes with his little brother's in a final desperate attempt to regain his sight. In doing so, Madara acquired a permanent Mangekyō Sharingan, devoid of all its weaknesses including the deterioration of normal eyesight.

After regaining his sight, Madara participated in several battles with his subordinates, conquering every enemy that stood in his path and quickly building up his title as one of the most powerful and skilled ninja in the world. Eventually, his conquests would lead him to the Senju Clan of the Forest and its leader, Hashirama Senju, who would later be known as the First Hokage. Madara and Hashirama became more or less friendly rivals, engaging in battle on several occasions. Fighting Hashirama, whose superiority was well recognized by all clans, would drastically increase Madara's fame, and consequently increase the Uchiha's enemies. Faced with this reality, Madara knew sacrifices has to be made to protect his clan from the Senju and other opposing clans, and his little brother agreed to offering up his eyes to advance Madara's power. However, shortly afterwards, the Senju clan offered a truce, which the Uchiha accepted. Madara, on the other hand, opposed the truce which had made his little brother's sacrifice in vain. Nevertheless, Madara was forced to agree to the truce since the rest of the clan agreed to it. Soon after, their alliance made a pact with the Land of Fire, who wanted assistance in controlling their territory, thus giving birth to Konohagakure. Madara, who felt that the Uchiha was losing its credibility due to Senju becoming the Hokage, began pleading with his clan. Much to his dismay, the clan refused, instead accusing Madara of being greedy and taking the eyes of his little brother out of lust for power. Feeling betrayed, Madara left the village, only returning to challenge it and its leader Hashirama. Madara was defeated by Hashirama at the place which is now called the Valley of the End.