It was serialized in Kodansha's seinen manga magazine Monthly Afternoon from June 1993 to December 2012, with its chapters collected in 30 tankōbon volumes.

The series is set in Japan during the mid-Tokugawa Shogunate period and follows the cursed samurai Manji, who has to kill 1,000 evil men in order to regain his mortality.

Blade of the Immortal follows the deeds of Manji, a skilled rōnin who has a decisive advantage: no wound can kill him, except for a rare poison.

He becomes immortal at the hand of an 800-year-old nun named Yaobikuni, and is compelled by the death of his sister to accept the quest that will end his agelessness.

He has vowed to make amends by killing 1,000 evil men, and until he does Manji will be kept alive by "sacred bloodworms" (血仙蟲, kessen-chū), remarkable creatures that allow him to survive nearly any injury and reattach severed limbs even after hours of separation.

Manji crosses paths with a young girl named Rin Asano and promises to help her avenge her parents, who were killed by a cadre of master swordsmen led by Anotsu Kagehisa.

"[4] Written and illustrated by Hiroaki Samura, Blade of the Immortal started in Kodansha's seinen manga magazine Monthly Afternoon on June 25, 1993,[5] and finished on December 25, 2012.

[11] A sequel, titled Blade of the Immortal – Bakumatsu Arc (無限の住人～幕末ノ章～, Mugen no Jūnin Nakumatsu no Fumi), written by Kenji Takigawa and illustrated by Ryū Suenobu, with Samura's collaboration, was serialized in Monthly Afternoon from May 25, 2019,[12] to May 24, 2024.

[21] To preserve the integrity of his art, Samura requested the publisher Dark Horse Comics not to "flip" the manga, that is, reverse the pages as if in a mirror.

[24] Instead, Blade of the Immortal was modified for Western readers by the unusual method of cutting up the panels and rearranging them on the page in order to have the action flow from left to right.

[25] Although American industry practice has largely changed over to publishing translated manga in its original right-to-left orientation,[24] Blade of the Immortal had retained the labor-intensive cut-and-paste method.

[42] A novel, titled Blade of the Immortal: Legend of the Sword Demon (無限の住人 刃獣異聞, Mugen no Jūnin Ninjū Ibun), written by Junichi Ohsako, with illustrations by Samura, was released by Kodansha on July 18, 2008.

[44] On March 23, 2008, it was announced that an animated television series adaptation of the manga would be directed by Kōichi Mashimo and produced by Bee Train in 2008.

[55][56] In 2017, the manga was adapted into a live action film, directed by Takashi Miike with the screenplay by Tetsuya Oishi and starring Takuya Kimura as Manji.

[60] Blade of the Immortal won the Excellence Prize at the first Japan Media Arts Festival in 1997;[61] and the Will Eisner Comic Industry Award in 2000 for Best U.S.