Chepstow stands in an area which provides evidence of human settlement dating back to the Mesolithic period (c.5000BC). It is likely that there was a small Roman fort in or around the area of modern Chepstow, providing a crossing point on the River Wye between Gloucester and Caerwent. Following the departure of the Romans the site saw the development of the main port and market for southern Gwent, known as Striguil or Estrighoiel. In the immediate aftermath of the Norman Conquest the town was noted for its strategic importance, and in 1067 William the Conqueror ordered that the first marcher castle be built there; Chepstow Castle (NPRN 95237) still stands today and is the oldest stone castle in Britian.
In 1294 Striguil received a royal charter confirming its right to hold a weekly market and annual fair, which flourished in part due to its exemption from English taxation. During this period the town walls were completed (NPRN 302128). By the fourteenth century the town became known as Chepstow, from the Old English `ceap/chepe stowe?, meaning `market place?, and during the early nineteenth century an Assembly Room and Market House was built (NPRN 408610).
Chepstow retained its position as the foremost port in south Wales until the nineteenth century, when Swansea, Cardiff and Newport became more suitable for the bulk export of coal and industrial materials. It is now noted for its historic architecture, light industry, and position close to the Wye Valley and Forest of Dean.

K Steele, RCAHMW, 30 December 2008