User blog comment:765479/Taisho Era/@comment-39182006-20200208141311

The Hand Demon  complained that it had been locked up in this prison since the previous era when Tanjiro told him that we were in the Taisho era (1912-1926) knowing that the Meiji era lasted 44 years (1868-1912), we can think that the manga takes place between 1918 and 1926