Older than China
Lafcadio Hearn
Kwaidan: Stories and Studies of Strange Things
Most of the Japanese literature about butterflies, excepting some poetry, appears to be of Chinese origin; and even that old national aesthetic feeling on the subject, which found such delightful expression in Japanese art and song and custom, may have been first developed under Chinese teaching...
It is possible also that some weird Japanese beliefs about butterflies are of Chinese derivation; but these beliefs might be older than China herself. The most interesting one, I think, is that the soul of a living person may wander about in the form of a butterfly.