Itachi was born into the Uchiha clan as the eldest son of Mikoto and Fugaku Uchiha and was praised bởi all as the best of his generation, a genius above all others, even bởi the standards of the battle-adept Uchiha clan, Itachi's prowess far outshone their own. However, few could understand him. When he was only four, Itachi had already witnessed countless lives Mất tích due to the Third Shinobi World War, which emotionally traumatised him and turned him into a pacifist.During the Nine-Tails' attack on Konoha, Itachi was left alone to take care of his infant brother Sasuke and promised to protect him no matter what. In the anime, it was shown that during their childhood, Itachi made a game of collecting paw prints of mèo with his brother. The last paw print to be collected was Nekomata's, who Itachi had defeated and asked him to fight Sasuke with all his might when Sasuke got older. At age 7, Itachi graduated from the Academy at the hàng đầu, đầu trang of his class after only one year, mastered the Sharingan at age 8, passed the Chūnin Exams at age 10, enrolled in ANBU half a năm later and became captain bởi 13. At some point in time in their childhood, Sasuke helped Itachi on one of his missions to capture a giant boar. Itachi told Sasuke to avoid his vital points. He then threw kunai with explosive tag around the boar, to confuse it and to give Sasuke an opportunity to shoot the boar. Sasuke, however, missed completely. After Sasuke apologised, Itachi told him he needs to train more.Itachi was praised highly bởi his father, who saw the family's future in Itachi and hence inadvertently neglected his younger son. However, during this time Itachi showed great affection towards his little brother and even encouraged his father to come to the Academy enrolment ceremony for Sasuke, something their father had otherwise forgotten, caught up an important mission that would establish Itachi a place in the ANBU ranks. When the Uchiha clan began planning to overthrow Konoha, Itachi, as an ANBU, was tasked with spying on the village. Knowing that a coup d'état would only lead to another Ninja War, Itachi began spying on the Uchiha instead, passing on information to the Third Hokage and Konoha elders. During this time he began to act strangely, not attending the clan meetings, speaking out against the clan, and becoming the prime suspect for the murder of his best friend Shisui Uchiha, who was drowned in the Naka River. In reality, Shisui died after entrusted his remaining Mangekyō Sharingan to Itachi, the other having been taken bởi Danzō. Due to this the clan Mất tích hope in Itachi, and his father began shifting his focus to Sasuke instead. Meanwhile, the Third's attempts to negotiate a bloodless end to hostilities between the two parties were proving ineffective so, against Hiruzen's wishes, Danzō Shimura and the Konoha Council ordered Itachi to wipe out the Uchiha clan. Before the fateful night arrived, Itachi discovered the existence of Tobi — under the guise of a vengeful Madara Uchiha — who was attempting to rekindle the flames of war in Konoha. In return for not attacking Konoha, Itachi offered to help him claim vengeance against the Uchiha for turning their backs on him decades earlier; Tobi agreed. Itachi slaughtered his entire clan overnight, including his friends, superiors, family, and lover. However, he spared Sasuke, because he could not follow through with the orders to kill his little brother. Instead, he made himself out as a villain, who had killed their innocent family only to test his capacity, and told Sasuke he was not even worth killing. In addition, Itachi told him, "You've always wanted to surpass me. That's why I'm going to let bạn live… if bạn wish to kill me, then hate me, despise me… and bởi all means flee, cling to your wretched life". Itachi also revealed to Sasuke the secret meeting place of the Uchiha, where Sasuke can learn the true history and purpose of the Sharingan. Itachi told him that in order to awaken the Mangekyō Sharingan, Sasuke had to kill the person closest to him, and that when they met again, they should have the same eyes. Sasuke managed to stand back up, awaken his Sharingan, and pursue Itachi. Upon reaching Itachi, he managed to knock off his forehead protector. Itachi shed a tear as he was picking up his forehead protector, then proceeded to incapacitate Sasuke, who awoke in the hospital, only remembering up to Itachi's speech. bởi doing all this, Itachi hoped Sasuke would take vengeance on him and become a hero to Konoha, thus redeeming the Uchiha name. Hoping that his little brother would someday be powerful enough to kill him, Itachi left the village as a traitor. Knowing that Konoha would still want to eliminate Sasuke, Itachi pleaded with the Third Hokage to keep Sasuke an toàn, két an toàn and threatened Danzō not to harm Sasuke hoặc else he would reveal everything he knew about Konoha's secrets to enemy nations. Itachi joined Akatsuki in order to keep an eye on the organisation, along with Tobi, in case either ever acted against Konoha, all the while planning for his death at Sasuke's hands. During his time in Akatsuki, Orochimaru tried to steal his body to gain the Sharingan, but Itachi trapped him in a genjutsu and severed his left hand.Itachi was further partnered with Kisame Hoshigaki, who initially tried to intimidate him. However, they eventually became good partners. Sometime after Orochimaru fled, Itachi helped recruit Deidara bởi beating him in battle using only genjutsu, to which Deidara swore vengeance.
At some point in time, Itachi contracted a fatal illness. He kept himself alive through the intake of various medicines and sheer "willpower", in the hopes of living long enough to die bởi Sasuke's hands.