Namazu, the earthquake-causing subterranean catfish of Japanese folklore, is a well-
known icon of earthquake folklore. Following the Ansei Edo Earthquake in late 1855,
anonymous entrepreneurs produced and sold hundreds of varieties of catfish picture
prints. Many of these 1855 prints were sophisticated expressions of thinly-veiled political
views, using the earthquake-catfish and other symbols as cover to avoid censure by the
military government. Primary sources indicate that the earthquake-catfish only began to
manifest itself in Japanese culture in the seventeenth century, and was not well known
until at least a century later.