The group comprises personal papers, being letters written by and received by the Griffith family, 1724-1943, letters of families such as Hughes of Gwydir, Weeg, Llwyn Gronw and Cae'rberllan, Roberts of Bryn y neuadd, Wynne of Garthmeilio and Plasnewydd, and others, 1680-1882, small diaries, pocket notebooks and almanacks containing memoranda and personal notes, 1701-1853, a few photographs, postcards and other memorabilia, 1901-[c. 1940], school papers, certificates and appointments, 1746-1920. The family members who are most frequently represented here are Jane Griffith (nee Hughes), John Wynne Griffith, Jane Griffith (nee Wynne), George Griffith, Edward Humphrey Griffith, William Henry Griffith and William Douglas Wynne Griffith. The letters, notebooks and diaries are illustrative of late eighteenth and nineteenth century life, particularly with regard to the family and household, social engagements, sporting activities, travel, elections, contemporary local and national events, domestic organisation and estate management.

The group consists of administrative records of the estates in Denbighshire, Flintshire, Caernarfonshire and Merionethshire, including rentals, 1658-1784, leases and related documents, 1756-1906, papers concerning crown rents, 1791-1845, enclosures and commons, 1802-1848, timber and mineral exploitation, 1748-1789, sporting rights, 1912, surveys and valuations, 1751-1880, maps and plans, 1776-1866 and estate accounts, 1708-1911.

Papers of Messrs Powles & Tyler of Monmouth, solicitors, including deeds, accounts and correspondence, 1683-1895, predominantly 1780-1880, relating mainly to Monmouthshire families; deeds and accounts relating to individual properties, mainly in Monmouthshire, 1614-1901; sale posters for properties, mostly in Monmouthshire, 1777-1860; shrievalty papers, 1824-1845; records of civil cases, 1762-1848; probate records, 1733-1900; insurance papers, 1737-1881; taxation papers, 1800-1871; insolvent debtors papers, 1807-1831; papers of Friendly Societies, 1833-1874; papers relating to industry, 1790-1872, transport, 1826-1913, and religion, 1804-[early 20th century]; election and electoral registration papers, mainly in Monmouthshire on behalf of the Conservative party, 1818-1885; personal papers, 1808-1895; and miscellaneous items, [c. 1250]-1886, including oriental documents, [early 19th century], acquired by Sir Leonard Twiston Davies, mainly the work of Persian poet, Mīzrā 'Abdu'l-Wahhāb of Eşfahān (d. 1828).