Papers of D. J. Williams, Llanbedr, Merionethshire, 1773-1949, comprising notebooks and other papers belonging to John Jones ('Tudur Llwyd') and John Peter, 'Ioan Pedr', 1773-1850; miscellaneous business papers, 1846-1903; notes, essays, books, and poems by D. J. Williams, 1911-1949; manuscripts of translations (by others) of books into Welsh, 1942-1945; notes and materials on the history of Llanderfel and Ardudwy, 1935-1938; manuscript and sources for Cyfres Chwedl a Chân, [1930s]; letters to D. J. Williams concerning children's stories, 1933-1949, from various authors; general correspondence of D. J. Williams, 1909-1941; papers relating to the translation into Welsh of school books and Welsh publications, 1932-1949; and radio scripts, stories, plays and lectures, by D. J. Williams and others [20th century].