is a Japanese light novel series by Hiro Arikawa, with illustrations by Sukumo Adabana. There are four novels in the series, though only the first novel is called Toshokan Sensō; the subsequent novels are named Toshokan Nairan, Toshokan Kiki, and Toshokan Kakumei. The novels were published by MediaWorks between February 2006 and November 2007. Two volumes of a spin-off series entitled have also been published by ASCII Media Works.

Two manga adaptations were published by Hakusensha and ASCII Media Works. A 12-episode anime adaptation produced by Production I.G aired on Fuji TV's Noitamina programming block between April and June 2008. Two Internet radio shows started in April 2008 meant to promote the series which are hosted by voice actors of the anime. An anime film by Production I.G was released on June 16, 2012. A live action film was released on April 27, 2013, with its sequel released on October 10, 2015.

By April 2008, the original four novels and volume one of the spin-off series have sold over 1.25 million copies in Japan. In 2008, Library War received the 39th Seiun Award for Best Japanese Long Work.

Plot The background of the plot is based on the Statement on Intellectual Freedom in Libraries that went into effect in Japan in 1954 (amended in 1979), and the terms are a little different from the Freedom of the Library Law that appears in Toshokan Sensō.

The simplified declaration:It is the most important responsibility of libraries to offer collected materials and library facilities to the people who have the Right to Know as one of their fundamental human rights. In order to fulfill their mission, libraries shall recognize the following matters as their proper duties, and shall put them into practice.

Libraries have freedom in collecting their materials. Libraries secure the freedom of offering their materials. Libraries guarantee the privacy of users. Libraries oppose any type of censorship categorically.

When the freedom of libraries is imperiled, we librarians will work together and devote ourselves to secure the freedom.

In Library War, the fourth chapter of the Freedom of Library Law states: <li> Libraries have freedom in collecting their materials. <li> Libraries secure the freedom of offering their materials. <li> Libraries guarantee the privacy of users. <li> Libraries oppose any type of improper censorship categorically. <li> When the freedom of libraries is imperiled, we librarians will work together and devote ourselves to secure the freedom. The details will be amended anytime according to the Media Betterment Act and its enforcement.

Story The premise involves the Japanese government passing the as law in 1989 which allows the censorship of any media deemed to be potentially harmful to Japanese society by deploying agents in the (MBC) with the mandate to go after individuals and organizations that are trying to exercise the act of conducting freedom of expression activities in the media. However, local governments opposed to the MBA establish armed anti-MBA defense force units to protect libraries from being raided by MBC agents under the Freedom of the Libraries Law.This line is always narrated by the leading voice actor of the show at the beginning. The conflict between MBC agents and library soldiers has continued to 2019, when the story begins. In accordance with the Japanese era calendar scheme, 1989 in Library War is rendered the first year of the fictional era, rendering 2019 as Seika 31.

Library War follows the life of Iku Kasahara, a new recruit in the Kantō Library Base who joined in 2019 after being inspired by a high ranking Kantō Library Defense Force member who saved a book she wanted to buy that was targeted for censorship. After joining, however, she finds the pace to be very demanding, and that her drill instructor Atsushi Dojo seems to have it in for her and working her harder than the other recruits. On multiple occasions, Kasahara shows herself to be reckless, particularly when she puts Dojo in danger by not securing a criminal in the base's library, and later getting involved with Media Betterment Committee agents despite not being a high enough ranked official; in both instances Dojo has to help her out of trouble. Despite these imperfections, Kasahara is enlisted into the base's Library Task Force, an elite group of soldiers who go through rigorous training in order to respond during difficult operations. This is partially due to Dojo realizing that he did not give Kasahara adequate training, so he gives his recommendation that she join the task force, of which he is a member, in order to correct this mistake on his part. Other recommendations come from the captain of the task force, Ryusuke Genda, and second class task force library officer Mikihisa Komaki who is the same rank as Dojo. Along with Kasahara, another new recruit named Hikaru Tezuka is also enlisted into the task force who is much more capable at the position than Kasahara. Kasahara continues to try her best in the face of difficult challenges while protecting the books she has sworn to protect. As the story progresses, a romance blooms and Iku and Dojo make romantic feelings for each other evident.

Library Team The , or (LDF), in Library War is a paramilitary organization in Japan which serves to defend libraries against the Media Betterment Act (MBA) enforced by the Media Betterment Committee (MBC) via Media Betterment Corps and other pro-MBA independent factions. Different from the normal , which performs librarian functions like modern librarians, the LDF's main goal is to provide self-defense from the MBC during library raids, though their jurisdiction only extends so far as in the confines of library facilities in connection with the LDF, meaning they cannot extend their effort even into the city where an LDF base is located. However, there are provisions around this, such as in accordance with Library Law Article 30 regarding book collection in that LDF Library Officers or above can choose to buy any book they want, even books targeted for censorship by the MBC. The LDF has ten bases throughout Japan in ten regions of Japan: Hokkaidō, Tōhoku, Hokuriku, Chūbu, Kantō, Kansai, Chūgoku, Shikoku, Kyūshū, and Okinawa. Each of the bases act under the provisions of the local government, and houses a public library where civilians can read and check out books.

In the early years of the conflict the library forces were not well organized, so coordination with neighboring forces was often delayed which caused problems in times of armed conflict. One such incident in Library War occurred on February 7, 1999, in Hino at the Hino Library which later became known as the . The incident was caused by an independent group which sided with the Media Betterment Committee raiding the Hino Library and caused the deaths of twelve people who were against the Media Betterment Act. Since that day, the library forces armed themselves in self-defense and have become much more organized; the public even acknowledges the LDF as having more combat experience than the police or the Japan Self-Defense Forces. The incident also caused the formation of library bases in ten regions, and the system of library forces in operation at the beginning of Library War.

The Library Defense Force has several branches which contribute to the organization as a whole. At the top is the Administrative Department where library administrators work doing daily administrative duties such as planning, organizing, staffing, budgeting, or directing. The Department of Defense works on defending against the Media Betterment Committee, and one section of the department consists of the Library Task Force, an elite group of soldiers who go through rigorous training in order to respond during difficult operations. At the Kantō Library Base, there are about fifty members in the task force. The Logistical Support Department works on stocking books and supplying the Department of Defense with military equipment, though it does not get involved with general outsourcing. There is also a Human Resources Department in charge of human resources, and an intelligence agency. There are approximately 30,000 members in the Library Defense Force throughout Japan. The German Chamomile is used in the insignia of Library Officers and above because the flower was a favorite of the late wife of the Library Defense Force commander Kazuichi Inamine.

Characters

Portrayed by: Nana Eikura A twenty-two-year-old member ranked in Library Clerk First Class. She is later promoted to Library Clerk Supervisor. She joined the Library Defense Force's Kantō Library Base in 2019 after being inspired by a high ranking Kantō Library Defense Force member who saved a book she wanted to buy that was targeted for censorship. She holds this unknown person in high regard, thinking of him as her "prince", and she wants to be an "ally of justice" as he was for her. As such, she has a strong sense of justice when it comes to freedom of expression and is willing to put her life on the line for the books she has sworn to protect. However, when she enters into recruit training, she finds it to be very challenging, especially since her drill instructor Atsushi Dojo, who seems to have singled her out for more attention and pushes her harder than most other recruits. In high school, she had been a member of the track and field team, so she has a lot of stamina and drive to continue with the Library Defense Force. When the story begins, Kasahara is a sub-par recruit who constantly prone to making critical mistakes and is not as knowledgeable about the cause she is in the middle of compared to others around her, mostly due to her not paying attention in lectures on the base. Despite these apparent flaws, she is recruited into the base's Library Task Force, an elite group of soldiers who go through rigorous training in order to respond during difficult operations. While at first she starts out slow, she soon becomes capable of clerical tasks in regard to working in the base's library, though she still finds it difficult to make a positive impression on Dojo, her superior officer. Later on, Kasahara finds out that Dojo, her superior, is actually her "prince" and she begins to warm up to him somewhat. By the end of the series, she marries Dojo and takes on his surname.

Portrayed by: Junichi Okada A twenty-six-year-old member of the Library Task Force and is ranked Librarian Second Class. He is tall, though is thought to be too short for Kasahara, despite her only being taller. He is very tough on Kasahara due to her not inspiring enough trust in him, and the fact that he believes he did not give her adequate recruit training. Part of the reason why he pushes Kasahara so much is that he sees his old self in her, and he is angry that she is bringing that back to him with such emotional force, despite him trying to forget about it. He later realises that he hurt her just so he could protect his fragile self. He often worries about Kasahara and even defends her from comments from others. By the end of the series, he marries Iku.

Portrayed by: Chiaki Kuriyama