In Japan, each era corresponds to the Emperor’s reign and is remembered for its idiosyncratic culture and zeitgeist. The Shōwa era, which lasted from 1926 to 1989, was arguably the most turbulent one yet, a witness to the nation’s shift from fascism to post-war reconstruction to the economic bubble of the late 1980s. Founded in the city of Ōme in 1999, the Showa Retro Packaging Museum is a time machine to the past, a gallery of nostalgic aesthetics and products of yesteryear. The collection, some donated by locals, includes movie…