Nantwich includes the hamlets of The Barony, Newtown in Nantwich, Shrewbridge, Snow Hill, Vauxhall and Wych House Bank. The population was 3,463 in 1801, 5,579 in 1851, 7,722 in 1901 and 8,843 in 1951.
The origins of the settlement date to Roman times, when salt from Nantwich was used by the Roman garrisons at Chester (Deva Victrix) and Stoke-on-Trent as both a preservative and a condiment. Salt has been used in the production of Cheshire cheese and in the tanning industry, both products of the dairy industry based in the Cheshire Plain around the town.
In the Domesday Book of 1086, Nantwich is recorded as having eight salt houses. It had a castle and was the capital of a barony of the earls of Chester, and of one of the seven hundreds of medieval Cheshire. Nantwich is one of the few places in Cheshire to be marked on the Gough Map, which dates from 1355–66. It was first recorded as an urban area at the time of the Norman conquest, when the Normans burned the town to the ground leaving only one building standing.
The Norman castle was built at the crossing of the Weaver before 1180, probably near where the Crown Inn now stands. Although nothing remains of the castle above ground, it affected the town's layout. During the medieval period, Nantwich was the most important salt town and probably the second most important settlement in the county after Chester. By the 14th century, the town held a weekly cattle market at the end of what is today is Beam Street, and it was also important for its tanning industry centred on Barker Street.
A fire in December 1583 destroyed most of the town to the east of the River Weaver. Elizabeth I contributed financially to the town's rebuilding, which occurred rapidly and followed the plan of the destroyed town. Beam Street was so renamed to reflect the fact that timber (including wood from Delamere Forest) to rebuild the town was transported along it.
During the English Civil War Nantwich declared for Parliament, and consequently it was besieged several times by Royalist forces. The final, six-week-long, siege was lifted following the victory of the Parliamentary forces in the Battle of Nantwich on 26 January 1644.
The salt industry peaked in the mid-16th century, with around 400 salt houses in 1530, and had almost died out by the end of the 18th century; the last salt house closed in the mid-19th century. The last tannery closed in 1974. The town's location on the London to Chester road meant that Nantwich began to serve the needs of travellers in medieval times. This trade declined in the 19th century, however, with the opening of Telford's road from London to Holyhead, which offered a faster route to Wales, and later when the Grand Junction Railway bypassed the town.
The Shropshire Union Canal runs to the west of the town on an embankment, crossing the A534 via an iron aqueduct. The basin is a popular mooring for visitors to the town. It joins the Llangollen Canal at Hurleston to the north. The town is approximately four miles south-west of Crewe and 20 miles south-east of Chester.
The parish church of Nantwich is St Mary's with original registers dating from 1539 for baptisms and 1576 for marriages.