Papers relating to Richard Rees ('Maldwyn', 1851-1927), of Machynlleth, Montgomeryshire, and Edward Walter Rees, ('Gwallter Dyfi', 1881-1940), of Carmarthen, including correspondence, 1874-1940; printed materials, 1866-1937; papers relating to the National Eisteddfod and the Gorsedd of Bards, 1909-1939; papers relating to the National Petition on the Legal Status of the Welsh Language, 1938-1939; papers relating to Maengwyn Calvinistic Methodist Chapel, Machynlleth, 1875-1920; and various papers relating to manifold aspects of Machynlleth life.