"SKENFRETH, a parish in the upper division of the hundred of Skenfreth, county Monmouth, 6 miles N.W. of Monmouth, and 24 from Hereford. The village, which is small and chiefly agricultural, is situated at the bridge over the river Monnow. In the vicinity is the ruin of Skenfreth Castle. It was of trapezium form, encircled by a curtain wall of immense thickness, and defended by six towers and a circular keep, but of which nothing now remains but the outer wall. The living is a vicarage in the diocese of Llandaff, value £215. The church is an ancient structure dedicated to St. Bridget, and has several stained windows." [Description(s) from The National Gazetteer of Great Britain and Ireland (1868)
Bradney, Joseph A. Sir. A history of Monmouthshire : from the coming of the Normans into Wales down to the present time / Pt.1,; The hundred of Skenfrith. London : Mitchell Hughes and Clarke , 1904. 144p.
Buckland, Kirstie. The Skenfrith Cope and its companions. Oxford] : [Pasold Research Fund], 1983. Reprint from: Textile history, 14 (2), 1983. Includes bibliographical references.
Churches and castles within the Grosmont, Skenfrith, and White Castle trilateral. Cross Ash, Gwent] : Cross Ash School,  20p.
Guide to Monmouth and the various objects of interest in and around it : including brief historical and descriptive notices of Monmouth, Raglan, Whitecastle, Skenfrith, and Grosmont Castles, Tintern Abbey, &c.. Monmouth : published by R. Waugh, [18--?] 77p.
Hopson, Mary. The Roman Catholic burial ground and former church at Coed Anghred, Skenfrith, Gwent. [Llanrothal, Monmouth] : Tregate Press,  192p.
Knight, Jeremy K. The three castles : Grosmont Castle, Skenfrith Castle, White Castle, Hen Gwrt medieval moated site. Cardiff : Cadw: Welsh Historic Monuments , 2000. 48p.
Levett, F G. The story of Skenfrith, Grosmont and St. Maughans with excursions to Llangattock-Vibon-Avel and Llanrothal. F.G. Levett, 1984. 250 leaves.
Maddock, M J. St. Bridget's Church, Skenfrith : historical notes. [Skenfrith] : St. Bridget's Church, 19--?]. 4p.
Portrait of a parish : Skenfrith. Gwent Family History Society Journal. No. 70 (June 2003), p. 9-10.
Remfry, Paul M. Skenfrith Castle 1066 to 1449. Malvern Link : S.C.S. Publishing, c2000. 47p.
Family Search have an interactive map called "England and Wales Jurisdictions 1851" showing parish (and other) boundaries with optional background maps such as Ordnance Survey. There is also a Search facility, do read the guidance notes to get maximum benefit from this useful resource. See here for further background information to assist in the interpretation of this data
Kain, R.J.P., Oliver, R.R., Historic Parishes of England and Wales: an Electronic Map of Boundaries before 1850 with a Gazetteer and Metadata [computer file]. Colchester, Essex: History Data Service, UK Data Archive [distributor], 17 May 2001. SN: 4348. Here is a gazetteer/finding aid plus a set of overview maps to accurately identify the position of parishes within the county.
You can see maps centred on OS grid reference SO455203 (Lat/Lon: 51.878589, -2.793124), Ynysgynwraidd / Skenfrith which are provided by: