Monmouthshire's turbulent medieval history on the Welsh Marches is reflected in its "fine collection" of castles, including that at Chepstow, "one of the great strongholds of Europe".

[11] The Silures proved among the most intractable of Rome's opponents; Tacitus described them as "exceptionally stubborn" and Raymond Howell, in his county history published in 1988, notes that while it took the Romans five years to subdue south-east England, it took thirty-five before complete subjugation of the Silurian territories was achieved.

[13] In south east Wales they encountered strong resistance from the Silures, led by Caratacus (Caradog), who had fled west after the defeat of his own tribe, the Catuvellauni.

The town was established in AD 75,[14] laid out in the traditional rectangular Roman pattern of twenty insulae with a basilica and a temple flanking a forum.

[16][b] The Romanisation of Monmouthshire was not without continuing civil unrest; the defences at Caerwent, and at Caerleon, underwent considerable strengthening in the late 2nd century in response to disturbances.

The Silurian identity was not extinguished: the establishment of a Respublica Civitatis Silurium (an early town council) at the beginning of the 3rd century testifies to the longevity of the indigenous tribal culture.

[23][d] For a brief period in the 11th century, Monmouthshire, as Gwent, became part of a united Wales under Gruffydd ap Llywelyn, but his death in 1063 was soon followed by that of his opponent Harold Godwinson at the Battle of Hastings, and the re-established unity of the country was to come from Norman dominance.

[25] The Norman invasion of South Wales from the late 1060s saw the destruction of the Kingdom of Gwent,[26] and its replacement by five Marcher lordships based at Striguil (Chepstow), Monmouth, Abergavenny, Usk and Caerleon.

De Braose proceeded to have his men massacre the Welsh, before sending them to burn Seisyll's home at Castell Arnallt and to murder his son, intending the obliteration of the indigenous Gwent aristocracy.

Seeking to re-establish Welsh independence, the revolt began in the north, but by 1403 Owain Glyndŵr's army was in Monmouthshire, sacking Usk[45] and securing a victory over the English at Craig-y-dorth, near Cwmcarvan.

Though for all purposes Wales had become part of the Kingdom of England, and the difference had little practical effect, it did begin a centuries-long dispute as to Monmouthshire's status as a Welsh or as an English county, a debate only finally brought to an end in 1972.

[51] This began a legal separation which continued until 1972; for example, the administrative county of Monmouthshire and the boroughs of Newport, Abergavenny and Monmouth were explicitly listed as being in England rather than Wales in first schedule of the Local Government Act 1933.

Following Henry VII's religious reforms, the county had a reputation for recusancy, with the strongly Catholic Marquesses of Worcester (later Dukes of Beaufort) at its apex, from their powerbase at Raglan Castle.

[53] The outbreak of war saw the county predominantly Royalist in its sympathies; Henry Somerset, 1st Marquess of Worcester expended a fortune in support of Charles I and twice entertained him at Raglan.

[54][55] John Arnold, member of parliament for Monmouth Boroughs in the late 17th century, was a virulent opponent of Catholics and pursued a policy of harassment from the 1670s.

[59] Industrialisation came early to Monmouthshire; the first brass in Britain was produced at a foundry at Tintern in 1568,[60] and the lower Wye Valley and the Forest of Dean became important centres for metalworking and mining.

Although his efforts were sometimes satirised, Gilpin established what became the conventional route down the "mazy course" of the River Wye, with visitors embarking at Ross-on-Wye, and sailing past Symonds Yat, and Monmouth, before the highlight of the tour, Tintern Abbey.

The abbey at Tintern inspired artists and writers; J. M. W. Turner painted it;[69] William Wordsworth committed it to verse;[70] and Samuel Taylor Coleridge almost died there.

[73] The noted architectural watercolourist Samuel Prout painted the bridge in a study dated "before 1814", now held at the Yale Center for British Art in Connecticut.

[75] Alfred Russel Wallace, a naturalist whose independent work on natural selection saw Charles Darwin bring forward the publication of On the Origin of Species, was born at Llanbadoc, outside Usk, in 1823.

[83] William Wilson Allen, who fought with the South Wales Borderers at the Battle of Rorke's Drift in 1879, is buried in Monmouth Cemetery, the only grave in the county of a holder of the Victoria Cross.

The Sugar Loaf (Welsh: Mynydd Pen-y-fâl or Y Fâl), located three kilometres (two miles) northwest of Abergavenny, offers far-reaching views; although its height is only 596 metres (1,955 ft), its isolation and distinctive peak shape make it a prominent landmark.

[105] Monmouth's coastline forms its southern border, running the length of the Severn Estuary from Chepstow in the east to the shore south of Magor in the west.

[131] Monmouth is also one of eight constituencies in the South Wales East electoral region, which elects four additional members, under a partial proportional representation system.

[137] The Diocese of Monmouth, within the Church in Wales, serves the area covered by the historic county, and its bishop, from 2019 Cherry Vann, is based at Newport.

[149] The county's main centres of population are served by a bus network, connecting Abergavenny, Monmouth, Chepstow, Raglan and Usk, with stopping points at smaller settlements on route.

Today, the canal is a popular route for leisure cruising but most of its length lies within the principal areas of Torfaen, Blaenau Gwent and Newport.

[201] The cuisine of Monmouthshire traditionally focused on its local produce, including lamb and mutton from sheep farming in the hillier north of the county,[202] poultry and game.

[227] The development of tourism in the late 18th century saw the writing of a number of histories of the area, which frequently combined the features of a guidebook with a more formal historical approach.

Coxe's preface explains the tour's genesis: "The present work owes its origin to an accidental excursion in Monmouthshire, in company with my friend Sir Richard Hoare, during the autumn of 1798.