Taishō era 大正時代
The reign of Emperor Taishō, 1912–1926, a short era of party politics and Western-influenced urban culture, in which Itō Seiu was active as a painter and researcher of Edo customs.
The Taishō era runs from July 30, 1912 to December 25, 1926, the reign of Emperor Taishō; English Wikipedia renders the name as “great righteousness.” Kotobank’s encyclopedia entry notes that historians sometimes use a wider frame of 1905 to 1925 and singles out “Taishō democracy,” the shift toward party government and wider political participation, as the era’s defining trait. Western popular culture spread in the cities, and the Great Kantō earthquake of 1923 marks a turning point.
Itō Seiu was active through these years. Japanese Wikipedia says that after the 1923 earthquake he set out to document Edo-period customs and became known as a researcher of historical manners. More in Meiji and Taishō: Itō Seiu and the art of seme-e.