Literary history is full of forgetting—both forced and natural. Manuscripts and books have been forgotten as a result of conquest, language changes, and politics. Other texts have been forgotten due to their physical condition: sole manuscripts are hidden away in archives, libraries burn, and paper disintegrates. Many medieval texts that are now central to the English literary canon, such as Beowulf, Piers Plowman, and the Book of Margery Kempe, were virtually unknown until the nineteenth, or even twentieth centuries. Later texts, from the eighteenth, nineteenth, and twentieth centuries, have been forgotten due to changes in taste, to their originally ephemeral nature, or to the sheer quantity of works that were published.