Historic county of Wales
Monmouthshire
Sir Fynwy
Black Mountains above, Severn below, the Usk running between.
Monmouthshire / Sir Fynwy changes dramatically from north to south. The Black Mountains rise in the north-east, while the Usk descends through broad agricultural country towards the Severn estuary. Westwards, a series of narrower valleys formed the setting for major coal and iron industries.
The result is a county of sharp contrasts: mountain and lowland, pastoral east and industrial west, river valley and estuary. Its geographical position also sits alongside an unusually complicated national history. Monmouthshire has profound Welsh territorial and cultural associations, but its historical England/Wales status cannot accurately be reduced to a simple timeless answer.
- England/Wales borderland
- Area: 542 sq mi
- Population: 514,723
- Rivers Monnow, Rhymney and Monnow form the county boundaries
- Formed from the cantrefs of Gwent Is-coed and Gwent Uwch-coed.
- County Top: Chwarel y Fan
County geography
Current Census
Contemporary Census profile
England and Wales Census 2021. Detailed contemporary statistics are available in the Geographic County Census Explorer.
- Population density
- 976.2 people per sq mi (376.9 people per km²)
- Population
- 528,647
The Usk through the heart
The Usk provides Monmouthshire with its strongest internal geographical thread.
It links mountain country with the broad central lowlands before opening towards the Severn, tying together landscapes which otherwise differ considerably.
Rural east, industrial west
Eastern Monmouthshire is predominantly agricultural and river-oriented.
The western valleys developed a markedly different character through coal and iron, creating densely settled industrial landscapes alongside the county’s older rural geography.
Between England and Wales
Monmouthshire’s territorial origins and cultural associations are strongly Welsh, and HCI groups it with the historic counties of Wales.
Historically, however, official practice was inconsistent. For centuries Monmouthshire was treated with England for some purposes, with Wales for others, and at times separately. Its earlier national status is therefore best described as genuinely ambiguous or anomalous.
County questions
Questions about Monmouthshire
Is Monmouthshire in England or Wales?
HCI groups Monmouthshire with the historic counties of Wales, and its territorial origins are Welsh. Historically, however, its position was unusually ambiguous, with official sources treating it differently for different purposes. The earlier question should therefore not be made artificially categorical.
Is Gwent simply another name for Monmouthshire?
No. Older Gwent, geographic Monmouthshire, later local-government areas using the Gwent name and lieutenancy geography are different territorial layers. Reuse of an ancient name does not make those territories identical.
County record
Names and continuity
- Formal name
- County of Monmouth
- Local name
- Sir Fynwy
- County day
- 25 September
- Foundation
- Early 16th Century
Monmouthshire and Sir Fynwy are forms associated with the county. Its enduring geography can be described clearly even while recognising that its historical national classification was unusually complex.