Originally known as `Lin', it is believed to be derived from the Celtic word for a lake or pool, and  records indicate that a large tidal lake covered the area.

Previously named Bishop's Lynn (Lenn Episcopi), in the 12th century the town was a part of the manor of the Bishop of Norwich. It ranked as the third port of England by the 14th century. Herbert de Losinga (bishop of Thetford) had the medieval town's St.Margaret Church built between Mill Fleet and Purfleet and authorised a market to be held. The prefix of Bishop's occurred following the issuance of a charter by a bishop - John de Grey of Norwich

Two warehouses of the Hanseatic League that were in use between the 15th and 17th centuries still survive.

Henry VIII's dissolution of  the monasteries in 1538, led the town and manor became royal property. The names King's Lynn (Lynn Regis) reflected this change. Through the export of corn the town became wealthy in the 17th century; the Henry Bell designed  Customs House was built in 1683.

The town's surviving 'South Gate' in London Road is one of the most conspicuous monuments of the town and is sometimes open for public access.

 Lynn had two 'Marts' 500 years ago and these  important trading fairs attracted overseas visitors from as far afield as Italy and Germany. Over the years these trading fairs became less important and the Mart's nature changed from a trading fair to a funfair. It also became an annual event.

King's Lynn is now part of the Borough of King's Lynn and West Norfolk.

King's Lynn Mart

For two weeks commencing on Valentine's Day February 14, the Tuesday Market Place  fills with the sounds of music, screaming youngsters and the generators powering rides. This is the 'Mart' fair.

Frederick Savage,  a local pioneered the application of steam power to fairground rides, barrel organs etc and went on to develop a unique industry manufacturing the power-driven roundabouts, swings and joy-wheels.