In the engi (writing about the history) of temples and shrines throughout Japan and local reports or history books, shinengo (itsunengo [era name really existed and taken out of official history], eras other than the era names set forth by the imperial court) often appears.
日本各地の寺社の縁起や地方の地誌・歴史書等には私年号（逸年号。朝廷が定めた元号以外の年号。）が多数散見される。