“The 1876 revisions of the National Bank Decree allowed would-be bankers to use the title ‘bank’, but it was only Mitsui who would immediately take this opportunity to establish themselves as a western-style modern bank. (Mitsui had earlier in 1872 planned to set up their own bank but were persuaded to support the government scheme of bringing about a national bank system.) In April 1876, Mitsui drafted the prospectus entitled The Case for the Establishment of Mitsui Bank which was accepted by the Finance Ministry. Mitsui Bank opened its doors on the first day of July 1876.
“In the prospectus, Mitsui were proud of ‘the business of the house of Mitsui being extistent for several hundred years.’ [But,] the ancient, distinguished name of Mitsui Gumi was abandoned without hesitation and the new business launched with the simple name Mitsui Bank.
– Japanese Banking: A History, 1859-1959, by Norio Tamaki, 2005