Berkeley was first recorded in 824 as Berclea, from the Old English for "birch lea".
Berkeley was a significant place in medieval times. It was a port and market-town, and the meeting place of the hundred of Berkeley. After the Norman Conquest, a Flemish noble named Roger de Tosny was appointed Provost of the manor of Berkeley by his brother-in-law (or perhaps uncle) Earl William FitzOsbern. His family took the name "de Berkeley", and it was he who began the construction of Berkeley Castle, which was completed by his son, also Roger. A younger son of the elder Roger, John de Berkeley, went north to Scotland with Queen Maud, becoming the progenitor of the Scottish Barclay family.
The parish of Berkeley was the largest in Gloucestershire. It included the tithings of Alkington, Breadstone, Ham, Hamfellow and Hinton, and the chapelry of Stone, which became a separate parish in 1797.
Berkeley lies midway between Bristol and Gloucester, on a small hill in the Vale of Berkeley. The town is on the Little Avon River, which flows into the Severn at Berkeley Pill. The Little Avon was tidal, and so navigable, for some distance inland (as far as Berkeley itself and the Sea Mills at Ham) until a 'tidal reservoir' was implemented at Berkeley Pill in the late 1960s.
https://www.revolvy.com/main/index.php?s=Berkeley%2C+Gloucestershire
Berkeley is linked to the River Severn by the Little River Avon that was navigable by small barges. There was a wharf at Berkeley Pill, located near the castle. This permitted local cross-river trade with the Forest of Dean, allowing the transport of coal from its mines to Berkeley.
Berkeley is a small market town in Gloucestershire, situated in the Severn Vale, 18 miles (30km) north of Bristol. The town is located about 1.5 miles (2.4km) to the south of the River Seven. It is dominated by Berkeley Castle, home of the Fitzhardinge family. The plan of the town has changed little since medieval times, with four main streets: Canonbury Street, High Street, Salter Street and Marybrook Street (previously named Maryport Street), first mentioned in 1492, 1575, 1575 and 1516 respectively. Overshadowed in wealth and prosperity by the nearby wool and cloth producing towns of the Cotswolds and Cotswold scarp, Berkeley was nevertheless important as a local market, trading centre and as the home of the Fitzhardinge family.
http://humanities.uwe.ac.uk/bhr/Main/Berkeley/sources.htm .
