Library War 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 Bessatsu Toshokan Sensō have also been published by ASCII Media Works.

Production I.G, Inc. is a Japanese animation studio and production enterprise. Headquartered in Musashino, Tokyo Production I.G was founded on December 15, 1987, by producer Mitsuhisa Ishikawa and character designer Takayuki Goto as "I.G Tatsunoko", a branch studio of the animation giant Tatsunoko Production, changing its name to the current Production I.G in September 1993. The letters I and G derive from the names of the company founders. Since 2007, Production I.G is a subsidiary of the IG Port holding company. Ishikawa was president and CEO of the studio until August 2022 when that position was given to George Wada with Ishikawa remaining as chairman of the company.