Monmouthshire ( ), also formerly known as the County of Monmouth ( ; ), was one of the thirteen counties of Wales that existed from 1536 until their abolition in 1974. Located in the south-east of Wales, on the border with England, its area now corresponds approximately to the present principal areas of Monmouthshire, Blaenau Gwent, Newport and Torfaen, and those parts of Caerphilly and Cardiff east of the Rhymney River.

The eastern part of the county was mainly agricultural, while the western valleys had rich mineral resources. This led to the area becoming highly industrialised with coal mining and iron working being major employers from the 18th century to the late 20th century. Its five largest towns were Newport, Cwmbran, Pontypool, Ebbw Vale and Abergavenny.

Monmouthshire's Welsh status was ambiguous between the 16th and 20th centuries, with it sometimes considered to be part of England during this time, such in as the Local Government Act 1933; its legal inclusion in Wales was clarified by the Local Government Act 1972, the same act that changed the structure of local government within the county.

History Formation The "county or shire of Monmouth" was formed from parts of the Welsh Marches by the Laws in Wales Act 1535. According to the Act the shire consisted of all Honours, Lordships, Castles, Manors, Lands, Tenements and Hereditaments, lying or being within the Compass or Precinct of the following Lordships, Townships, Parishes, Commotes and Cantrefs... in the Country of Wales:

Monmouth • Chepstow • Matherne (Mathern) • Llanvihangel (Llanfihangel Rogiet) • Magour (Magor) • Goldcliffe (Goldcliff) • Newport • Wentlooge • Llanwerne (Llanwern) • Caerlion (Caerleon) • Usk • Treleck (Trellech) • Tintern • Skenfrith • Grosmont • Witecastle (White Castle) • Raglan • Calicote (Caldicot) • Biston (Bishton) • Abergavenny • Penrose (Penrhos) • Grenefield (Maesglas) • Maghen (Machen) • Hochuyslade (possessions of Llanthony Priory)Ivor Waters, Chepstow Packets, 1983, , p.34

The Act also designated Monmouth as the "Head and Shire town of the said county or shire of Monmouth", and ordered that the Sheriff's county or shire court be held alternately in Monmouth and Newport.Section 3 of the Laws in Wales Act 1535 (27 Hen. 8. c. 26)

Boundaries and subdivisions

The county boundaries are the River Wye on the east, dividing it from Gloucestershire and the Rhymney River to the west dividing it from Glamorganshire, with the Bristol Channel to the south. The boundaries with Herefordshire to the northeast and Brecknockshire to the north were less well-defined. The parish of Welsh Bicknor, was an exclave of Monmouthshire, sandwiched between Gloucestershire and Herefordshire. The area was considered part of Monmouthshire until it was made part of Herefordshire "for all purposes" by the Counties (Detached Parts) Act 1844, while the Herefordshire hamlet of Fwthog (or Ffwddog) adjoining the Honddu Valley remained an exclave within Monmouthshire until 1891.F. A. Youngs Jr., Guide to the Local Administrative Units of England, Vol.II: Northern England, London, 1991

The county was divided into six hundreds in 1542: Abergavenny, Caldicot, Raglan, Skenfrith, Usk and Wentloog.

The county contained the three boroughs of Monmouth, Newport and Usk.Samuel Lewis (ed.), Monmouthshire, in A Topographical Dictionary of England, 1848, British History Online, accessed May 2, 2008

Civil parishes In the medieval period Monmouthshire was divided into the following civil parishes, listed by hundred (chapelries in italics): HundredParishesAbergavennyAbergavenny • Aberystruth • Cwmyoy (Llanthony) • Goytre • Llanddewi Rhydderch • Llanddewi Skirrid • Llanellen • Llanfair Kilgeddin • Llanfoist • Llangattock Lingoed • Llangattock nigh Usk • Llanhilleth • Llanover • Llansantffraed • Llantilio Pertholey (Bettws) • Llanvapley • Llanvetherine • Llanvihangel Crucorney • Llanvihangel Gobion • Llanwenarth • Mamhilad • Oldcastle • TrevethinCaldicottBishton • Caerwent • Caldicot • Chepstow • Christchurch • Goldcliff • Ifton • Itton • Langstone (Cat's Ash) • Llanfihangel Rogiet • Llanmartin • Llanvaches • Llanvair Discoed • Llanwern • Magor (Redwick) • Mathern • Mounton • Nash • Newchurch • Penhow • Penterry • Portskewett • Rogiet • St Arvans • St Brides Netherwent • St Pierre • Shirenewton • Sudbrook • Undy • Whitson • WilcrickRaglandBettws Newydd • Bryngwyn • Cwmcarvan • Dingestow • Kilgwrrwg • Llanarth • Llandenny • Llandogo • Llanfihangel Tor-y-mynydd • Llangovan • Llanishen • Llansoy • Mitchel Troy • Penallt • Penrhos • Pen-y-clawdd • Raglan • Tintern Parva (Tintern St Mary) • Tregare • Trellech (Trellech Grange) • WolvesnewtonSkenfrithDixton • Grosmont • Llangattock Vibon Avel (Llanfaenor) • Llangua • Llantilio Crossenny • Llanvihangel Ystern Llewern • Monmouth (Overmonnow) • Rockfield • St Maughans • Skenfrith • Welsh Bicknor • WonastowUskGwernesney • Kemeys Commander • Kemeys Inferior • Llanbadoc • Llanddewi Fach • Llandegveth • Llanfihangel Llantarnam • Llanfihangel Pontymoile • Llanfrechfa • Llangattock juxta Caerleon • Llangeview • Llangwm (Llandevaud • Llangwm Isaf) • Llangybi • Llanhennock • Llanllowell • Llantrisant • Monkswood1 • Panteg • Tredunnock • Trostrey • UskWentloogeBassaleg • Bedwas • Bedwellty • Bettws • Coedkernew • Henllys • Machen • Malpas • Marshfield • Michaelston-y-Fedw • Mynyddislwyn • Newport • Peterstone • Risca • Rumney • St Brides Wentloog • St Mellons 1extra-parochial, but still had its own church

Municipal reform Monmouth and Newport were reformed as municipal boroughs with elected town councils by the Municipal Corporations Act 1835. Usk continued as an unreformed borough until its final abolition in 1886.

New forms of local government were established in the urban areas of the county with the setting of local boards under the Public Health Act 1848 and Local Government Act 1858. The Public Health Act 1875 divided the rural areas into rural sanitary districts.

An administrative county of Monmouthshire, governed by an elected county council, was formed in 1889 under the terms of the Local Government Act 1888. The act directed that where urban sanitary districts straddled county boundaries they should be placed entirely in the administrative county which had the majority of the urban sanitary district's population. Along the boundary between Monmouthshire and Brecknockshire were four urban sanitary districts which straddled the county boundary: Brynmawr, Ebbw Vale, Rhymney, and Tredegar. The majority of Brynmawr's population was in Brecknockshire, and so the southern parts of Brynmawr within Monmouthshire were transferred to the administrative county of Brecknockshire. For the other three urban sanitary districts the majority of the population was in Monmouthshire, which therefore gained from Brecknockshire the Beaufort and Rassau areas of Ebbw Vale, the Dukestown area of Tredegar, and the Llechryd area of Rhymney.

The county council was based in Newport, rather than the historic county town of Monmouth. In 1891 the borough of Newport achieved county borough status and therefore left the administrative county, although the administration of the county council continued to be based at Shire Hall, Newport. In the same year the parish of Fwthog was transferred to both the administrative and geographic county of Monmouthshire.

Under the Local Government Act 1894, the administrative county was divided into urban and rural districts, based on existing sanitary districts.

Municipal boroughs Monmouth Urban districts Abercarn • Abergavenny • Abersychan • Abertillery • Bedwellty • Blaenavon • Caerleon • Chepstow • Ebbw Vale • Llanfrechfa Upper • Llantarnam • Nantyglo and Blaina • Panteg • Pontypool • Rhymney • Risca • Tredegar • Usk Rural districts Abergavenny • Chepstow • Magor • Monmouth • Pontypool • St Mellons

In 1899 Abergavenny was incorporated as a borough. Two further urban districts were formed: Mynyddislwyn in 1903, and Bedwas and Machen in 1912. The County of Monmouth Review Order 1935 revised the number and boundaries of the urban and rural districts in the administrative county. A new Cwmbran urban district was formed by the abolition of Llanfrechfa Upper and Llantarnam UDs, Abersychan and Panteg UDs were absorbed by Pontypool urban district, and Magor and St Mellons RD was formed by a merger of two rural districts.

The county boundaries provided the basis of the boundaries of the new Diocese of Monmouth, created in October 1921 following the disestablishment of the Church in Wales from the Church of England in April 1920. The Diocese covered all of the County of Monmouthshire but also included the Parish of Cyncoed in north-east Cardiff, a situation which continues in 2023.

The last major boundary change to affect the administrative county came in 1938 when the Monmouthshire parish of Rumney was incorporated into the city and county borough of Cardiff. However, the geographical Monmouthshire/Glamorgan and England/Wales border remained the Rhymney River.

Local government reform The administrative county of Monmouth and county borough of Newport were abolished in 1974 under the Local Government Act 1972. The successor authority, with minor boundary changes, was titled Gwent. Some border parishes became part of the new Rhymney Valley district of Mid Glamorgan or the Cardiff district of South Glamorgan.

Ambiguity over status

Background The historic county covers an area roughly contiguous with the medieval Kingdom of Gwent's core cantrefi of Gwent Uch-coed (Upper Gwent), Gwent Is-coed (Lower Gwent), and Gwynllŵg.R. J. Mansfield, Forest Story, 1965

Gwent became part of the Kingdom of Morgannwg in the 10th century, and part of the unified Kingdom of Wales under Gruffydd ap Llywelyn. Following the Norman invasion of Wales, Monmouthshire was subject to the Marcher Lords, and was not subject to English law.R. R. Davies, Conquest, Coexistence and Change: Wales 1063–1415 (Oxford University Press, 1987), ch. 14.John Davies, A History of Wales, 1993, Following the Acts of Union the land which is today called Monmouthshire was undisputedly in Wales.

The 16th to 19th centuries

The Laws in Wales Act 1535 (27 Hen. 8. c. 26) integrated Wales directly into the English legal system and the "Lordships Marchers within the said Country or Dominion of Wales" were allocated to existing and new shires. Some lordships were annexed to existing counties in England and some were annexed to existing counties in Wales, with the remainder being divided up into new counties, one of which was Monmouthshire.

Although the original Laws in Wales Act 1535 specifically includes Monmouthshire as being in the "Country or Dominion of Wales", the Laws in Wales Act 1542 (34 & 35 Hen. 8. c. 26) enumerates the Welsh counties as twelve in number, omitting Monmouthshire from the count. Monmouthshire was made directly responsible to the courts of Westminster rather than falling under the Court of Great Sessions in Wales. According to historian John Davies, this arrangement was the origin of the belief that the county had been annexed by England rather than remaining part of Wales. Davies disagrees, and says, "Monmouthshire was no less Welsh in language and sentiment than any other eastern county". Moreover the belief that Monmouthshire was somehow specially annexed to England is not consistent with the wording in the Act "That his said Country or Dominion of Wales shall be, stand and continue for ever from henceforth incorporated, united and annexed to and with this his Realm of England", making it clear that the whole of Wales was being "annexed" to England, not just Monmouthshire.The Laws in Wales Act 1535 (A.D. 1535 Anno vicesimo septimo Henrici VIII c. 26)