Sakumo Hatake

, also known as, is the father of Kakashi Hatake.

Background
Sakumo came from a clan well-known for its uniquely powerful chakra, a trait which he held stronger than any other clan member with the possible exeption of his son. According to the Fourth Hokage, the legendary White Fang had a reputation that surpassed even the Sannin in comparison. But, he fell into disgrace after botching a mission that caused Konohagakure to suffer great losses. Despite knowing how critically important completing the mission was, Sakumo chose the lives of his comrades over the success of the mission. He failed the mission and was discredited by both Konoha and the very same teammates he rescued. Dishonored, Sakumo fell into a deep depression, as well as a drop in his skills. Eventually, he committed suicide, which caused Kakashi to lead his life strictly according to the Ninja Code.

Appearance
Repeatedly, Sakumo's appearance has been compared to that of Kakashi, albeit without the Sharingan or the mask. He possesses the same style and colored hair with the addition of a long pontail. His facial features are more distinquished compared to Kakashi's visible ones.

Personality
Sakumo was a very kind and loyal man. Despite his tremendous fame and power as a ninja, he was a very humble man with a deep love for his family. His powers and kindness made his only son Kakashi truly look up to and idolize him. He had a deep devotion to his country and an even greater commitment to his allies and loved ones to the point he would put their well-being before anything else. His commitment was so great that he would sacrifice the completion of a mission in order to save his teammates which led to him being a public figure of hate and ridicule.

Kakashi Gaiden
During Team Minato's mission to destroy a crucial bridge, Minato explained to Obito about Sakumo and why Kakashi was how he was. After better understanding Kakashi, Obito felt sorry for Kakashi, who seemed compelled to restore honor to the Hatake clan. When their teammate Rin was captured by Stone ninja and Kakashi was determined to complete the mission rather than save Rin, Obito shocked Kakashi by revealing he knew about Sakumo, and even stated he agreed with Sakumo's decision. Obito was able to help Kakashi see even if Sakumo completed the mission, he would never be able to live with himself knowing he let his precious friends die. This compelled Kakashi to help Obito save Rin.

Rescue Gaara arc
When Kakashi and his team arrive in Sunagakure, he is instantly attacked by Chiyo who mistakes him for his father. It is implied that Sakumo killed Chiyo's son and his wife, during the war with the country.

Pain Invasion arc
During the battle against Pain, as Kakashi feels himself losing strength and consciousness, Kakashi finds himself in an area of darkness, where Sakumo meets up with his son to talk of his life.

Abilities
Like his son, Sakumo was a gifted shinobi praised for his talents in the ninja arts even by the likes of Minato Namikaze, the Fourth Hokage. In battle, Sakumo was a truly powerful shinobi, his prowess at least rivaling that of the Sannin. The mere idea of facing Sakumo brought fear to enemies, as shown from the reaction of an Iwagakure shinobi initially believing Kakashi to be his father. Like the rest of his clan, he had a unique chakra that was infamously strong and adaptive but much stronger than any other clan member except for maybe Kakashi. His primary weapon during battle was tanto called the White Light Chakra Sabre that when put in culmination with his already powerful chakra, enhances the strength of his chakra to the point it emitted a trail of white light from the blade when swung, earning him the nickname "Konoha's White Fang". After he died, he left his tanto for Kakashi, which was later on cut in half when Kakashi fought an Iwagakure shinobi.

Trivia

 * Due to his close resemblance to his father, Kakashi's mouth may be the same as his fathers shown in the picture above.
 * Sakumo also left his summoning scroll for Kakashi, which contained the ninja hounds contract.