Theses and dissertations :
- Aull, Charlotte Homes, Ethnic Nationalism in Wales, An analysis of the factors governing the politicization of ethnic identity, 1978.
- Chapman, William, The aesthetic of Jean Cocteau, 1955.
- Evans, Gwilym J., John Morris-Jones : His place in the 1886 literary revival, 1945.
- Gray, Owenna, A Survey of earthworks on the Isle of Anglesey, 1984.
- Griffiths, Jeremy, Lincoln Cathedral : Thornton MS 91, 1977.
- Gwilym, Lowri, Theory and criticism in the Welsh literary revival with special reference to contemporary periodicals, 1891-1919, 1979.
- Hughes, R. E., Daniel Silvan Evans, Aspects of Welsh Lexicography in the Nineteenth century.
- Hughes, William Richard, A survey and record of the cottages and buildings of Felin-Nant, 1982.
- Hughes, Zuzana, Some problems of elderly people in North Wales, 1975.
- Jackson, Robert Wyn, The Growth of Caernarvon : a study in Historical Geography, 1949-1950.
- Jones, Arthur, An investigation into the economics of livestock insurance, c. 1927.
- Jones, Ernest Mansel, Theories of Consumption, with reference to demand for and production of food-stuffs in Great Britain, 1939.
- Jones, Llewelyn, An edition of the correspondence of the First Marquess of Anglesey relating to the General Elections of 1830, 1831 and 1832 in Caernarvonshire and Anglesey, 1956
- Jones, Alun R., A critical study of the literary works of Lewis Morris, 1701-1765, 1997.
- Jones, Nia Lynn Powell, Plas Newydd - The study of a landed estate, 1999.
- Kenyon, Elizabeth B., The slate industry and its place in the industrial structure of North West Wales, 1951.
- Lloyd, Eluned C., The influence of the Methodist Movement on Social life in Wales, 1921.
- Loesch, Katharine T., Dylan Thomas : Welsh Poetic Syntax.
- Luff, Carol A., The growth of the Anglo-Irish sea link in Holyhead and its effect upon the economic and demographic aspects of the community, 1972.
- O'Kelly, Kathleen Magdalen, A Demographic study of central Snowdonia and its coastlands in the nineteenth century, 1961.
- O'Rahilly, Cecilia, Inter-relations of Ireland and Wales, 1919.
- Owen, Goronwy Price, Translations of William Powell in NLW Ms Peniarth 321, 1988.
- Owen, Prys Eifion, The establishment of the county intermediate schools in Caernarvonshire, 1957.
- Owen, Prys Eifion, The Development of the bilateral system of secondary education in Caernarvonshire, 1939 to date, 1961.
- Owen, Rhys, The history of the contribution of the Church of England to elementary education in Caernarvonshire up to 1870, 1940.
- Owen, W. T., The life and thought of Dr Edward Williams, with special reference to his influence on Welsh and English Nonconformity.
- Parry, Robert John, Second Hague Conference : The British attitude to the second Hague Conference : a study of newspaper opinion in England, 1906-1907, 1937.
- Parry, Robert Palmer, A study of the education, life and work of Sarah Winifred Parry (Winnie Parry) 1870-1953, including a bibliography of her work, 1980.
- Pierce, Gwladys, A critical estimate of Sir John Wynne's History of the Gwydir Family as an historical account, 1912.
- Rees, William Henry, The vicissitudes of the Welsh language in the Marches of Wales, with special reference to its territorial distribution in modern times, 1947.
- Rhodes, John N., The London Lead Company in North Wales, 1970.
- Tate, Stephen, A catalogue of small finds from the Bronze ell wreck, 1989.
- Thomas, Eifiona Elisabeth, The Socio-Economic Context of Agricultural and Ecological Change in the Llyn Peninsula, 1993.
- Thomas, Heather Janette, Children should be seen and not heard. Victorian childhood - the Journals of Margaret Hay Williams, 1997.
- Thomas, John Alun, House of Commons. An inquiry into the change in the character of the House of Commons, 1832-1901.
- Turner, Stephen, Theological Themes in the English Works of Williams, Pantycelyn, 1981.
- Williams, J. Gwynn, Sir John Vaughan Chief Justice of the Common Pleas, 1952.
- Williams, William Philip, Wales and the French Revolution : The Influence of the French Revolution on the Political and Social Life of Wales, 1925.
- Wright, E.G., Bishop Humphrey Humphreys (1648-1712) - A study of the literary and antiquarian movements in Wales in the 17th and early 18th centuries, 1948.