WebHistory of Japan. Reiwa ( Japanese: 令和, pronounced [ɾeːwa] ⓘ or [ɾeꜜːwa] [1] [2]) is the current and 232nd era of the official calendar of Japan. It began on 1 May 2019, the day on which Emperor Akihito 's eldest son, Naruhito, ascended the throne as …