The Japanese National Library dates back to the nineteenth century. In 1872, the Imperial Library was founded. It was institutionalized that one copy of every Japanese publication had to be made available to the library. The foundation of libraries for the members of the National Diet (the Parliament at the time) followed in 1890.
In 1948, the collections of both institutes were put together in the National Diet Library. The library’s main task continues to be assisting the members of the Japanese Parliament in their work. In addition to this, it also serves the general public with its comprehensive public library facilities.
The National Diet Library has three facilities. Tokyo Main Library and the International Library of Children's Literature are in Tokyo. In 2002, the vast, modern Kansai-kan was opened near the city of Kyoto; the sizeable collection of the National Diet Library is being digitized in this new complex.