Haslemere is not mentioned in the Domesday Survey of 1086, probably because it formed part of the Manor of Godalming. It is first recorded in a document dated 1221 by which time it already had a market. In that year Henry III granted the Manor of Godalming, including Haslemere, to the Bishop of Salisbury. In 1393 Richard II confirmed the grant of a weekly market on a Wednesday and a five-day fair.

At some obscure date in the medieval period Haslemere acquired the right to send two burgesses to Parliament, a right which was confirmed by Queen Elizabeth in 1596. The most famous of the town's M.P.s was James Oglethorpe, who first entered Parliament in 1722. Ten years later he sailed for America with a party of 120 settlers to found the colony (now state) of Georgia, named after the then king, George II.

Freehold qualifications meant that the electorate of Haslemere was very small and therefore at elections there was plenty of opportunity to abuse the system. Oglethorpe was ousted in the election of 1754 when extra freeholders, who therefore had the right to vote, were created by temporarily sub-dividing various properties including a pub called the Red Cow, then situated in what is now Petworth Road. Haslemere was clearly a 'rotten borough' and its parliamentary rights were swept away by the Reform Act of 1832.

Thereafter, Haslemere slipped into obscurity only to be rescued by the opening of the railway from Godalming to Havant in 1859. The Haslemere area became famous for the health-giving quality of the air, especially on the heights of Hindhead above the town, and the rich and famous soon sought out land on which to build. The novelist, George Eliot, lived at Shottermill for a time and Tennyson had a house, Aldworth, built just over the border in Sussex. Sir Arthur Conan Doyle, creator of Sherlock Holmes, was amongst a number of other literary figures who moved to the area. In the 1890s supporters of the Arts and Crafts Movement also set up a variety of cottage industries around the town. These included weaving houses, a tapestry works and a pottery.

Amongst others who came to live in Haslemere was Robert (later Sir Robert) Hunter, who joined forces with Octavia Hill and Hardwicke Rawnsley to found the National Trust in 1895, the name of the organisation being his idea. Dr (later Sir) Jonathan Hutchinson, a famous surgeon, started an educational museum at his home, Inval, in 1888. The museum moved to East Street, now Petworth Road, in 1895 and then to its present premises in the High Street in 1926. It remains an important asset to the town to this day.