Although John Milton’s poetry represents only about one-fifth of his total literary production, the prose works are more obscure, largely because he wrote in genres that no longer appeal to a large audience. Milton’s prose is usually valued mostly for what it reveals about his biography and his thought. His most prominent theme was liberty—religious, domestic, and civil. The following examples are notable: five antiprelatical tracts (1641-1642); four tracts justifying divorce (1643-1645); and five pamphlets defending the English Puritan cause against the monarchists (1649-1654). The tract Of Education (1644) and the classical oration upholding freedom of the press, Areopagitica (1644), are the most familiar titles among the prose works. The remaining titles consist largely of academic exercises, letters, additional pamphlets, works of history, and treatises. Milton left in manuscript at his death a Latin treatise on religion, De doctrina Christiana libri duo Posthumi (1825), a work that provides valuable clarification of his religious beliefs.