Kakashi Hatake is a shinobi of Konohagakure's Hatake clan. In the anime, Obito is seen to be crushed by a rock giving Kakashi his Sharingan. He was assigned to Konoha's Anbu by his sensei and the Fourth Hokage, Minato. In the span of 3-5 years he would be apart of the Anbu and when Minato passed away, Hiruzen relieved Kakashi from his duties as an Anbu because he felt that people with 'good-hearts' shouldn't be tasked with the ruthless missions Danzo appointed them with.
Background
Early Life
Because his mother died when he was very young, Kakashi was raised during his early years by his father, Sakumo. Sakumo was famed throughout the shinobi world, having saved Konoha on at least one occasion; Kakashi in particular revered his father. During one of Sakumo's missions - after Kakashi was enrolled in Konoha's Ninja Academy - Sakumo made the decision to save the lives of his teammates rather than complete the assignment. The mission's failure had disastrous consequences for the Land of Fire, causing many in Konoha, including the teammates he saved, to vilify him for abandoning his duties. Disgraced, Sakumo committed suicide. Seeing what his father went through and determined not to make the same mistakes, Kakashi decided that following the shinobi rules must always take priority.
In the Academy, Kakashi earned top grades, earning him recognition as a prodigy and the best of his generation. Ultimately, he became very popular amongst his peers. With his talents soon being recognised, at age 5, Kakashi graduated from the Academy at the top of his class in a single year. Upon becoming genin, he and his classmates, Rin Nohara and Obito, were teamed together under the leadership of Minato Namikaze. In the anime, Minato gave the team a bell test at its formation, assigning the three to take the two bells he kept on his person. Minato often held back less against the prodigious Kakashi than with Rin and Obito so they couldn't obtain the bells without teamwork. Unfortunately, Kakashi realised this, only using Obito and Rin as a means to an end to obtain the bells. Nonetheless, Minato passed them because they accomplished the goal of the test by working as a team. Minato did encourage them to improve their teamwork afterwards, a message that Obito and Rin took to heart, but fell upon deaf ears with Kakashi. Team Minato would go on many missions during its career, but Kakashi's devotion to the rules often made him difficult to work with; Obito, already jealous of Kakashi's natural talent and popularity, was frequently at odds with him about this behaviour. At age 6, Konoha officials allowed Kakashi to compete in the Chūnin Exams with his team, which he passed by defeating Might Guy and became a chūnin.
Third Shinobi War
Konoha eventually became embroiled in the Third Shinobi World War. As part of the war effort, Team Minato was assigned to destroy the Kannabi Bridge in Kusagakure in order to cut off Iwagakure's supply line. Minato was needed on the front lines at the time, leaving Kakashi, recently promoted to jōnin at age 12, in charge. Before embarking on the mission, Minato and Rin gave him presents to celebrate his promotion; Obito forgot to get him anything. Shortly after entering Kusa, they encountered an Iwa-scout, Mahiru. Kakashi tried to eliminate him with his new jutsu, Chidori, but the attack speed left him vulnerable to counter-attack, forcing Minato to step in, save Kakashi, and kill Mahiru himself. Before leaving them, Minato advised Kakashi to not use the Chidori again.
Kakashi saves Obito
Kakashi, Rin, and Obito continued further in to Kusa. They were eventually found by Mahiru's teammates, Kakkō and Taiseki, who kidnapped Rin in order to find out what their mission was. Obito immediately suggested that they rescue her, but Kakashi elected to abandon Rin, believing it was more important to finish the mission before concerning themselves with her safety. Obito refused to go along with this and went off to save Rin by himself. Before he left, he told Kakashi that Sakumo had been a hero and that, although it was bad to abandon one's mission, it was worse to abandon one's teammates. Kakashi began carrying out the mission alone, but ultimately decided that Obito was right and went to join him. He arrived in time to save Obito from Taiseki with his White Light Chakra Sabre, which he inherited from his father.
Taiseki turned invisible and tried launching a sneak attack on Obito. Kakashi protected him, but his left eye was badly damaged in the process. In that moment, Obito awakened his Sharingan and used it to kill Taiseki. They then entered the cave where Rin was being held, drove off Kakkō, and released Rin from the genjutsu he placed her under. Kakkō retaliated by forcing a cave-in and Kakashi, due to his damaged eye, was struck in his blind spot and had difficulty avoiding the falling rocks. Before he could be crushed by a large boulder, Obito pushed him out of the way, becoming trapped instead. Unable to get free and knowing his injuries were too serious to survive, Obito decided to make his last act giving Kakashi the present he forgot to give him earlier: his Sharingan to replace the eye Kakashi lost.
After Rin transplanted Obito's Sharingan into him, Kakashi confronted Kakkō. His White Light Chakra Sabre was destroyed during the ensuing fight, but he succeeded in killing Kakkō with Chidori; due to the Sharingan's heightened vision, Kakashi was finally able to handle its speed. He went back to where Obito and Rin were, but Iwa reinforcements soon arrived and started constricting the rubble. Obito asked Kakashi to take Rin away and keep her safe, which Kakashi did, leaving Obito behind. As the Iwa-nin started surrounding them, Kakashi attacked them for as long as he could, holding them off until Minato eventually tracked them down and finished off the rest. Minato assisted them with destroying the Kannabi Bridge and then returned with them to Konoha to mourn Obito's death. Despite many from the Uchiha clan being against Kakashi wielding a Sharingan as he had no blood-ties to them, Fugaku Uchiha, the Uchiha head, chose to honour Obito's dying actions and let Kakashi keep his gift.
Kakashi unintentionally stabs Rin
During a later mission, Rin was kidnapped by Kirigakure. Kakashi was eventually able to rescue her and started taking her back to Konoha. Along the way, Rin revealed that Kiri had sealed the Three-Tails into her body with the intention to, once she inevitably lost control of it, have it unleashed on Konoha and destroy the village from within. In order to prevent this from happening, Rin begged Kakashi to kill her, but he refused, unwilling to break his promise to Obito to protect her and hoping to find some other solution. When Kiri-nin caught up with them and made false efforts to retrieve her, Kakashi fought them off with his renamed Chidori, the Lightning Cutter. During one of these attacks, Rin jumped in front of Kakashi's attack, dying by his hand so that Konoha would be safe. The trauma of this caused his Sharingan to evolve into a Mangekyō Sharingan shortly before Kakashi passed out. He was later found by Konoha reinforcements, but none could explain the slaughter of all the Kiri forces, not knowing of Tobi's actions.
Anbu Carrer
Kakashi Joins the Anbu
Because he'd lost two teammates in such a short timespan, his role in Rin's death, and his failure to honour Obito's last request by protecting her, Kakashi dropped into a depression. In the anime, many believed he purposely killed Rin to prevent her from leaking information, earning him the nickname "Friend-Killer Kakashi". Many, especially those in Anbu believed he would kill a comrade without hesitation if it was for the sake of completing the mission. He would also spend his days avoiding friends and former classmates and at night he would be haunted by dreams of himself killing Rin again. Minato, now the new Hokage, tried to help Kakashi emerge from the darkness he'd fallen into after Obito and Rin's deaths by assigning him to the Anbu in order to have him close in an attempt to alleviate his pain. Kakashi did well in the Anbu, eventually becoming a captain and the leader of Team Ro. However, his successes were owed to his cold behaviour and his ruthlessness in combat, signs that he was still upset by Rin's death. Minato therefore tried a different tactic: assigning Kakashi to protect Minato's wife, Kushina Uzumaki, during her pregnancy. Kakashi carried out his duties faithfully, monitoring Kushina from the shadows whenever she left her home. During his time off, he would visit Rin's grave and Obito's engraving to tell them his regrets and how life was going without them.
Kakashi and others held back from protecting Konoha
During the Nine-Tailed Demon Fox's Attack, Kakashi and many of Konoha's other young ninja were prevented from helping defend the village, instead being confined within a barrier to keep them safe. Minato eventually saved the village from the Nine-Tails, but at the cost of his and Kushina's lives. After which, Danzō Shimura approached a grieving young Kakashi, noting that it was Hiruzen Sarutobi's orders for the children, even high-ranking ninja like Kakashi, to not help battle the Nine-Tails, ultimately preventing Kakashi from possibly saving Minato and Kushina. Convincing an emotional Kakashi that the Third was not best for the future of the village, Kakashi agreed to join Danzō's Root division and spy on the Hokage for him. During a mission, Kakashi encountered another Root member codenamed "Kinoe" who was able to use Wood Release. Knowing that Wood Release was unique to the First Hokage, Kakashi broke in to the Hokage Residence to see what he could learn about this anomaly. The Third caught him, but freely gave him the information he wanted: Konoha had tried to recreate the Wood Release powers in the past, but abandoned the project for killing too many test subjects. The Third then mused that the Nine-Tails might have been defeated and Minato saved had the research been successful.
From this meeting with the Third, it became clear to Kakashi that the Third was not the ineffectual, passionless leader Danzō had made him out to be. Moreover, Danzō had not used Kinoe to try and stop the Nine-Tails' attack. Realising he had picked the wrong side, Kakashi told the Third about Danzō's plans to assassinate him and, the following day, personally lured out the assassins, of whom Kinoe was one. Kakashi easily defeated him, but chose to spare his life in the belief that he would become a valuable ally in the future. Kakashi attempted to resign from the Anbu afterwards for working against the Hokage, but the Third insisted his service was invaluable and made Kakashi his right-hand man.
Kakashi unable to stop Orochimaru
From investigating a series of disappearances, Kakashi provided a lead and it was discovered that Orochimaru was behind the Wood Release research that produced Kinoe. In the anime, Kakashi attacked Orochimaru when the Third Hokage failed to apprehend him, but he was paralysed by Orochimaru's killing intent and Orochimaru escaped. Kakashi followed him once he regained his composure, but was captured by the Iburi clan, who were loyal to Orochimaru. Kinoe, their ally, convinced them to let him interrogate Kakashi. Once alone, Kinoe confided that Danzō was making his own plans against Orochimaru and, with help from Yukimi, helped Kakashi get free. Kakashi later planned to use Yukimi to capture Orochimaru, since she was of great importance to him. Later, Kakashi explained that Yukimi's blood could temporarily bestow Orochimaru with the Iburi clan's smoke transformation, allowing him to slip across the border. Overhearing that, Yukimi slipped away and returned to the cave. Orochimaru ultimately killed most of the Iburi clan before escaping yet again, but Kakashi, recognising that Kinoe's relationship with Yukimi is much like his relationship with Rin was, helped keep her safe. Kakashi decided to leave and not report anything about the Iburi or Root's involvement.
Kakashi continued to investigate Orochimaru over the following years, eventually locating one of his secret labs three years after the latter's defection. While there, he was attacked by Kinoe, who Danzō had sent to take his Sharingan. Kakashi tried to reason with him by stating that friendship should take higher priority than the mission. When Kinoe accused Kakashi of violating that creed by killing Rin, enraged by that comment, Kakashi overpowered him and decided to bring him before the Third Hokage. Before they could leave, one of Orochimaru's snake experiments escaped its test tube and attacked the duo. As Kinoe was taken captive, Kakashi managed to slay the creature. While saving Kinoe, the creature's corpse began emitting a poisonous vapour which quickly infected Kakashi. Kinoe got Kakashi out safely and, having accepted Kakashi's words, gave Kakashi an antidote and chose to abandon his mission whilst leaving Kakashi a message about it. When Kakashi woke up, he knew Danzō would punish Kinoe for insubordination and asked the Third for help. With the Third's permission, Kakashi forced his way into Root headquarters and stopped Danzō from applying a cursed seal to Kinoe. As Root forces started to surround them, the Third showed up to personally authorise Kakashi's actions, and further negotiated Kinoe's release from Root. Kakashi added Kinoe, now with the new codename "Tenzō", to Team Ro.
Kakashi and Itachi Assassinate the Prajñā Group.
Two years later, Itachi Uchiha was added to Team Ro. Kakashi and Itachi were at one point assigned to observe a meeting between Konoha and the Land of Woods. When the Land of Woods' Prajñā Group tried to betray the Konoha forces, Kakashi and Itachi moved in and defeated them. Although Kakashi was impressed by Itachi's abilities, he warned him against his merciless approach and encouraged him on the importance of friends. Sometime later, Itachi asked Kakashi if dead friends' requests should be honoured, which Kakashi said they should. Itachi was eventually promoted out of Team Ro and replaced by Yūgao Uzuki. Shortly afterwards, Team Ro was sent to the Uchiha clan's compound with orders to pacify a brewing rebellion, only to find the entire clan dead. When news emerged that Itachi was responsible and that he had killed his best friend, Shisui Uchiha, in pursuit of power, Kakashi lamented his failure to have had a better influence on Itachi.
Kakashi resigns from the Anbu
Because of what happened with Itachi, the Third Hokage felt that individuals with kind hearts did not belong in the Anbu. He therefore thanked Kakashi for his years of service and relieved him of his duty, returning him to the standard forces. Over the years, he was placed in charge of several teams of Academy graduates, but none ever demonstrated the teamwork he considered to be so important. In the anime, he started worrying that his own methods were too harsh, but from seeing how his former underlings that he previously failed prospered due to his teachings, his faith was reaffirmed.
Personality
Kakashi's cold heartedness
Since his early childhood, Kakashi was very independent and self-confident, at times even appearing arrogant and condescending. Despite that, Kakashi was very perceptive and intuitive, quickly realising the situation for what it was. After his father's death, Kakashi became more stern, aloof and cold toward others, following all the rules to the letter, chastising any who disobeyed them and being willing to abandon his comrades to finish missions. As an adult, Kakashi typically has a relaxed and almost bored attitude, not prone to getting too worked up about anything or by anyone. Despite his increasingly growing reputation and prowess as a ninja, Kakashi has shown no signs of arrogance, and is rather modest about his abilities. He is habitually tardy, showing up when it suits him, using excuses that convince nobody, and later leaving for equally poor reasons. Though Kakashi wants others to believe this is how he always acts, he only does so for matters that aren't of particular importance.
Kakashi suffering from PTSD
In truth, Kakashi is rather a solitary and matter-of-fact person. Kakashi is still just as apathetic as he was during his youth, often speaking bluntly about sensitive topics and occasionally ignores his fellow classmates, whenever he passed by them. He is alone for most of his spare time, spending hours visiting Rin Nohara's grave or the Memorial Stone where Obito Uchiha's name is engraved. He tells them about his life, recent events in Konoha, and others they knew, but mostly he shares his regrets that they cannot be with him or that their deaths were his fault. In the anime, after Rin died, Kakashi went through a period of post-traumatic stress disorder, having nightmares about her death and growing depressed whenever others mentioned her. Over time, Kakashi comes to accept that Rin chose to die, so his guilt instead became more about his broken promise to Obito to keep Rin safe. This fact causes Obito's apparent death to weigh more heavily on him, compounding the regret he feels about what his personality was even hours before Obito seemingly died. Kakashi feels that, had he cared about teamwork and friendship in the same way that Obito did, Obito's "death" might have been avoided. Thinking it would ease his pain, Minato convinced Kakashi to join the Anbu. During his time in the Anbu however, Kakashi gained a reputation for his cold-bloodedness. As noted by Kurenai Yūhi, Kakashi suffered with suicidal thoughts during his Anbu career, with his reckless fighting style and lack of self-care being deemed as Kakashi being in a hurry to die.
Obito's apparent death profoundly changed Kakashi. More particularly, he became committed to teamwork and always places teammates' well-being above the mission's: he believes goals can be accomplished more effectively together, asking for help when he needs it, providing help when it is requested of him, and praising allies when they deserve it. An abuse of one's teammates is the only thing that can makes Kakashi cast aside his normally stoic demeanour, causing him to attack without mercy or his usual sense of sportsmanship. He expects his prospective students to demonstrate this same devotion to teamwork, which none until Team 7 were able to do; despite the high failure rate, the Third Hokage agrees with Kakashi's choice to require it. Kakashi becomes fond of all Team 7's members, even Sasuke Uchiha, to the point of blaming himself for Sasuke's criminal acts and his team's growing rift over it throughout Part II. He holds out hope that Sasuke will correct his behaviour, and for his patience he is able to see Team 7 reunified when Part II ends.
Kakashi & Guy competing in their usual "contests"
Might Guy has considered Kakashi his rival ever since they first met in the Academy. Despite his father's warning that Guy might someday prove stronger than him, Kakashi didn't think much of Guy at the time. Guy took this as a challenge and began striving to earn Kakashi's approval so as to show that his perseverance could be just as good as Kakashi's natural genius. When Guy would suggest contests to test how their abilities compared, Kakashi would respond with indifference, only fuelling Guy's desire to defeat his "cool, hip, and trendy" personality. At the start of Part I, Kakashi's score is 50 wins and 49 losses, though even when Guy takes the lead the score difference remains the same; considering that their competitions range from eating contests to Rock, Paper, Scissors, the score isn't truly representative of anything. Kakashi eventually comes to consider Guy one of his closest and most reliable friends, and by the end of the Fourth Shinobi World War he acknowledges that Guy has surpassed him. In the following years during his role as Hokage, Kakashi continued to dutifully work to progress the village. At the same time, he still believes that even in times of peace, no one should become a ninja without appreciating the importance of it.
Kakashi's obsession with the "Icha Icha" series
When he first meets his students on Team 7, Kakashi claims to have many hobbies, none of which he chooses to share at the time. He is known to be an avid fan of the Icha Icha series of novels; he always has one of the books with him and regularly reads it, even while talking to others. Naruto Uzumaki identifies Icha Icha as one of Kakashi's few weaknesses, which he is able to take advantage of during a bell test by threatening to spoil the ending of the newest book in the series, forcing Kakashi to shut his eyes and ears and thereby leave himself vulnerable. Although most people he knows are aware of how much he likes Icha Icha, Kakashi is seemingly uncomfortable sharing the books with others, to the point of growing embarrassed by the presumably adult content when he is forced to read passages aloud.
Following his retirement from active duty, Kakashi has become much more laid-back and relaxed, to the point of being unbothered by events and people surrounding him. His speech mannerisms and tone also resemble those of an old man. While retaining his seriousness in any and all important events, Kakashi willingly attempts to evade any responsibilities during his free time, such as when he attempted to evade Boruto's pleas for training. Furthermore, Kakashi also enjoys having others perform the most basic of chores on his behalf, such as roping Boruto into helping him with shopping duties, and initially refusing to help with Sabure and Yubeshi's issues with their respective grandparents until being promised a rare first edition of an Icha Icha volume, with an extended ending.
New Era
Academy Arc
Kakashi faces Nue.
In the anime, when learning about the mysterious attacks on the village, Kakashi begins investigating the incident, and learns that it involves a Root project. Upon reporting his findings to Naruto at the Hokage's Office, the two discuss the investigation with Shikamaru. Realizing the culprit planned to unleash the Nue on the village now that it was nearing completion, Kakashi went in search of the rogue student. Arriving at Senju park, Kakashi immediately severed the creature's tail, resulting in the spontaneous emergence of dozens of smaller tails, which it used to steal chakra from Sai's men. After saving them, Kakashi organized the team to hold off the creature. As Naruto arrives, Kakashi stops him from fighting, explaining that the creature's intention was to gather enough chakra to produce a powerful explosion to destroy the village. As the shinobi attempt to subdue the beast, it teleports away, much to Kakashi's surprise. Kakashi deduced that while this creature was a summoning, it uniquely existed normally in a separate dimension, leaving others unable to follow it.
Ability
Ninjutsu
Purple Lighting
Kakashi typically uses Purple Electricity to strike targets from a distance, though he does sometimes use it through direct contact, as when he places his hand on spilled alcohol in order to transmit Purple Electricity throughout the surrounding area. He can modulate the intensity of the Purple Electricity, creating a blast strong enough to remove a target's explosive vest but without setting off the explosive or otherwise affecting the target. Conversely, he is later shown using all his chakra to perform a Purple Electricity powerful enough to induce the rain clouds he's falling through to start producing rain.