Llangibby Castle estate records, including court rolls of manors in Monmouthshire, 1262-1911, Glamorgan, 1675-1739, Gloucestershire, 1427-1595, and Somerset, 1609-1691; title deeds, mainly Monmouthshire, 1217-1930, and correspondence, mainly 18-19 cent.; important letters and papers relating to the civil war in Monmouthshire; and manuscripts aquired by the family, including drafts and copies of Modus Tenendi Parliamentarum and Observata Parliamentaria by Henry Elsynge, junior (1598-1654), clerk to the House of Commons, together with minutes of the House of Commons, 1624-1626, calendar of the Journal of the House of Lords, 1647-1768, copies of the Journals of the House of Commons, 1547-1701, index to parliamentary proceedings, temp. Edward III-Edward IV, and, 1724-1743, civil war tracts, the journal of the missionary Dr Joseph Wolff, 1832, 'Prif Achae holh Gymru Benbaladr' in the autograph of Sir Thomas Wiliams, Trefriw, 1578-1609, a seventeenth-century collection of Welsh poetry by the principal 'cywyddwyr'; a memoir of Richard Robert Jones ('Dic Aberdaron', 1780-1843) in his own autograph; English sermons and miscellaneous notes by Rev. Edmund Jones, Pontypool, a sermon notebook of Rev. Philip Henry (1631-1696), the eminent Nonconformist divine, a survey of the lands of Henry, earl of Pembroke, in Glamorgan and Monmouthshire, 1570, and a survey of lands in the lordship of Usk, 1619; pedigree rolls of Sir Roger Williams of Penrhos, Monmouthshire, compiled by Thomas Jones ('Twm Siôn Catti'), 1591, and of the Williams family of Llangibby Castle, probably compiled by Sylvanus Morgan.

A manuscript monograph, [1878], entitled 'Some Notice of William Herbert, first Earl of Pembroke of the present creation', by J[ames] E[dward] Nightingale, F.S.A. (ff. 1-59). It was published, under that title, in The Wiltshire Archaeological and Natural History Magazine, 18 (October 1878), 81-131. The notice places particular emphasis on the politics of the time, in which Herbert played a prominent role, and on his Wiltshire connections.
The text is complete except for some two paragraphs (corresponding to the top of p. 114 in print), missing due to the bottom of f. 36 having been cut away, and a single sentence (top of p. 128) missing from f. 55. There are manuscript emendations throughout, including some revisions supplied as pasteovers (ff. 11, 21, 22, 23, 33, 42, 47); footnotes have been inserted on paper flaps attached to page margins (ff. 2-3, 5, 8, 12, 14, 16-17, 19-20, 22, 23-24, 25-30, 32-35, 37-44, 46, 48-49, 52-53, 56, 57, 59), and occasionally as separate leaves (ff. 6a, 6b, 24a). Also included are earlier drafts of a few sections of text and footnotes (ff. 22a, 22b, 43a, 56a, 61-62) and notes, references and transcripts of related letters and documents (ff. 60 recto-verso, 61 verso-64).