The group comprises letters written by members of the Griffith family of Garn, mainly the family of John Wynne Griffith, and close relatives, 1724, 1783-1876, with many details of family life, social activities, travel abroad, the children's school and university days, the progression of John Wynne Griffith's sons in their careers and assistance to their father in managing the estate, and acquaintance with other well-known families in north-east Wales, such as Clough, Kirkwall, Shipley, Jones of Llysmeirchion and Wynne of Plasnewydd, and letters from other correspondents addressed to various members of the Griffith family, 1733-1943, on many different subjects, the most frequently recurrent being estate business, particularly disputes over enclosures and encroachments, rights on crown lands, purchase of property and questions of title, legal and financial complications of the Plasnewydd estate trust, Denbigh borough and parliamentary elections, contemporary national and local events during the Napoleonic Wars, and public duties of individuals.

The group comprises papers recording the history, organisation and administrative procedures of local government institutions in Denbigh, Holt and Ruthin [post-1719]-1847, Denbigh town council elections, 1865, 1887, 1921, borough elections in Denbigh and parts of Flintshire, [c. 1742], [c. 1803], 1806, 1813, and draft petitions and speeches on topics of national political interest, 1814-1926. Some of the papers include substantial lists of burgesses.