First, let's look at the background to the establishment of the Institute.
Since the late Edo and Meiji periods, Kokugo Kokuji Mondai (national language and script problems) had been discussed from various standpoints as important issues for the country.
Notable contributions include "Kanji Onhaishi no Gi (Proposal for the abolition of kanji)" (1866, Keio 2) by Hisoka Maejima, who advocated writing only in hiragana, "Moji o Kaikansuru Gi (Proposal for the reform of characters)" (1869, Meiji 2) by Yoshikazu Nanbu, who advocated using the Roman alphabet, "Yoji o motte Kokugo o Shosuru No Ron (Discussion on writing the Japanese language with Western characters)" (1874, Meiji 7) by Amane Nishi, and "Moji no Oshie (Teaching of characters)" (1873, Meiji 6) by Yukichi Fukuzawa, who advocated limiting the number of Kanji to be used.
Meanwhile, the government established the National Language Investigation Committee in the Ministry of Education (1902, Meiji 35), the Temporary National Language Investigation Committee (1921, Taisho 10), the National Language Council (1934, Showa 9), etc. These bodies discussed the standard language, the reduction of Kanji, the use of Kana, the rules for romanization, etc.