was a Japanese warrior. As  of the Shinsengumi, he resisted the Meiji Restoration and fought to his end.

Background
 was born on May 31, 1835, in the Ishida village, Tama region of Musashi Province (present day Ishida, Hino, Tokyo), Japan. He was the youngest of ten children and his father Hijikata Yoshiatsu (Hayato), a well-to-do farmer, died a few months before his birth. His eldest brother Tamejiro, was born blind and as a result, could not inherit the family property. His third older brother Daisaku (later Kasuya Ryojin), was adopted to another family and would later become a physician. His eldest sister Shuu died when he was about three years old and his mother Etsu also died when he was six years old, and he was therefore raised by his second older brother Kiroku and sister-in-law.

He was apparently tall compared to the average Japanese men of the period, and it is said that he was very handsome. He was said to be spoiled at an early age and was alleged to be mean to all but his friends and family. This changed when a 21-year-old swordsman from the Aizu clan known for opposing the Reformists was forced to commit seppuku. When Hijikata attended the man's funeral, he apparently cried in public.

Hijikata spent his youth selling his family's Ishida san'yaku (medicine for treating injuries such as bruises and broken bones) while practicing his self-taught kenjutsu. His brother-in-law, Satō Hikogorō, who was married to his older sister Nobu, managed a Tennen Rishin-ryū dojo in Hino; through Satō, Hijikata later met Kondō Isami and was formally enrolled at the Tennen Rishin-ryū's Shieikan in 1859. Although Hijikata himself never fully mastered the Tennen Rishin-ryū, it is said that he managed to develop the "Shinsengumi-Kenjutsu" fighting style from the Tennen Rishin-ryū.

An arrangement was made by his eldest brother Tamejiro for him to marry Okoto, the daughter of the shamisen shop owners. Since he had already planned to join the Rōshigumi with Kondō Isami, Hijikata told them that after he got a promotion, he would carry out his marriage.

Shinsengumi period

In 1863, Hijikata and Kondō Isami joined the Rōshigumi in Edo, they arrived in Mibu, Kyoto and remained there as the Mibu Rōshigumi while the rest returned to Edo. Later, when Mibu Rōshigumi was renamed as the Shinsengumi, Kondō and two other men, Serizawa Kamo and Niimi Nishiki, became joint leaders of the group, and Hijikata served as one of the deputy leaders. Shinsengumi served as a special police force in Kyoto that fought against the Reformists under Matsudaira Katamori, the Daimyō of Aizu.

However, Serizawa and Niimi began fighting, drinking, and extorting money from merchants in Kyoto, which started to tarnish the reputation of Shinsengumi and earned the group the derogatory nickname of. Hijikata found enough proof against Niimi in these matters and ordered him to commit seppuku on October 19. Later on October 30 (or October 28) at night, Hijikata and the selected Shinsengumi members went into the house of Yagi Gennojō and assassinated Serizawa, his mistress Oume, and one of his followers Hirayama Goro, with Hirama Jūsuke been the only survivor who fled that night. Kondō became the sole leader of Shinsengumi, with Yamanami Keisuke as his Vice-Commander.  During the Ikedaya incident in the evening on July 8, 1864, Hijikata led a second group of 23 Shinsengumi members after Kondō's to help arresting a group of shishi at the Ikedaya Inn.

Some time after the Zenzaiya incident, Yamanami Keisuke tried to leave Shinsengumi, despite the regulation against deserters. As a result, he committed seppuku with Okita Sōji as his Kaishakunin on March 20 (lunar calendar February 23), 1865; and Hijikata took over as Vice-Commander. Due to his position in the Shinsengumi, which would be dangerous for anyone close to him, Hijikata felt that he had no choice but to cancel his marriage engagement with Okoto. Although he later had many lovers, he never came close to making a commitment to any of them.

The Shinsengumi grew to 140 men, which included a number of farmers and merchants whose livelihood would be threatened if the Tokugawa shogunate was overthrown. The regulations set up by Shinsengumi within Kyoto were strict and Hijikata was known to be harsh in enforcing them, hence his nickname:. Even within the Shinsengumi itself, regulations were strictly enforced by Hijikata. As usual, deserters and traitors were forced to commit seppuku.

Hijikata owned, among others, a sword signed "Izumi no Kami Kanesada" (和泉守兼定), made by the 11th and last generation Aizu Kanesada (1837-1903).

Together with the rest of the Shinsengumi, Hijikata became a hatamoto in 1867 and took the name of Naitō Hayato (but reverted to his original name after Kondō was captured and executed during the Boshin war). He was given the rank of Yoriai (寄合格 Yoriai-kaku) in early 1868.

Boshin War

Following the Boshin War in 1868, Kondō and Hijikata led the Shinsengumi in their final battles against the new government and fought in the Battle of Toba–Fushimi in January 1868. The Shinsengumi returned to Edo and was later reformed into a unit known as the  and departed from Edo for Kōfu Castle on March 24 upon orders to suppress the uprisings there. But while on the way there, they received news on March 28 that the Kōfu Castle was taken by Imperial Court forces led by Itagaki Taisuke and later settled at the town of Katsunuma five miles east of Kōfu.

On March 29, 1868, Kondō, Hijikata and the Kōyō Chinbutai resisted an attack by the Imperial forces at the Battle of Kōshū-Katsunuma for about two hours but lost, and they were scattered and fled to Edo.

On April 11, 1868, Kondō, Hijikata and the Kōyō Chinbutai departed Edo again and later set up a temporary headquarters at the Kaneko family estate, northeast of Edo. They later moved to a new headquarters in Nagareyama on April 25, 1868.

During the training at Nagareyama on April 26, 1868, the Kōyō Chinbutai were caught by surprise by the 200 strong Imperial forces led by Vice-chief of Staff Arima Tota of Satsuma Domain and Kondō was ordered to go with them to their camp at Koshigaya. He was later brought to Itabashi on April 27, 1868, for questioning. On the same day Hijikata went to Edo to see Katsu Kaishū and asked for his help in getting a pardon for Kondō. On the following day, a messenger arrived at Itabashi with a letter seemingly written by Katsu requesting that Kondō's life to be spared, but the messenger was arrested and the request was denied.

Following his trial on April 30, 1868, Kondō was executed at Itabashi execution grounds on May 17, 1868. Hijikata, convalesced from a foot injury sustained at the Battle of Utsunomiya Castle, brought Kondō' head to Aizu and was said to have personally supervised the erection of Kondō's grave memorial at Tenneiji Temple.

Following the Battle of Bonari Pass, the next day on October 7, 1868, Hijikata met Saitō Hajime at the Inawashiro Castle and stayed at the Saitoya inn in Wakamatsu. When Hijikata decided to retreat from Aizu, Saitō and a small group of Shinsengumi parted with Hijikata and continued to battle in the Battle of Aizu until the very end. Hijikata and his rest of the Shinsengumi went to Sendai, where he joined up with Enomoto Takeaki's fleet.

He knew he was fighting a losing battle, and told the physician Matsumoto Ryōjun:
I am not going to battle to win. With the Tokugawa government about to collapse, it would be a disgrace if no one is willing to go down with it. That is why I must go. I will fight the best battle of my life