The town centre is situated in a valley through which the River Darent flows, and where the old road from London to Dover crossed: hence the name, from Darent + ford. Dartford became a market town in medieval times and, although today it is principally a commuter town for Greater London, it has a long history of religious, industrial and cultural importance. It is an important rail hub; the main through-road now avoids the town itself.
In prehistory, the first people appeared in the Dartford area around 250,000 years ago: a tribe of prehistoric hunter-gatherers whose exemplar is called Swanscombe Man. Many other archaeological investigations have revealed a good picture of occupation of the district with important finds from the Stone Age, the Bronze Age and the Iron Age.
When the Romans engineered the Dover to London road (afterwards named Watling Street) it was necessary to cross the River Darent by ford, giving the settlement its name. Roman villa were built along the Darent valley, and at Noviomagus (Crayford), close by. The Saxons may have established the first settlement where Dartford now stands. Dartford manor is mentioned in the Domesday Book, written after the Norman invasion in 1086. It was owned by the king.
Wat Tyler, of Peasants' Revolt fame, might well have been a local hero, although three other towns in Kent all claim the same, and there are reasons to doubt the strength of Tyler's connection to Dartford though the existence of a town centre public house named after him could give credence to Dartford's claim though Dartford cannot claim a monopoly on public houses named after Tyler.
It is possible that Dartford was a key meeting point early in the Peasants' Revolt with a detachment of Essex rebels marching south to join Kentish rebels at Dartford before accompanying them to Rochester and Cantebury in the first week of June. Although lacking a leader, Kentishmen had assembled at Dartford around 5 June through a sense of county solidarity at the mistreatment of Robert Belling a man claimed as a serf by Sir Simon Burley. Burley had abused his royal court connections to invoke the arrest of Belling and despite a compromise being proposed by bailiffs in Gravesend, continued to demand the impossible £300 of silver for Belling's release. Having left for Rochester and Canterbury on 5 June, the rebels passed back through Dartford, swollen in number, a week later on 12 June en route for London.
The sixteenth century saw significant changes to the hitherto agricultural basis of the market in Dartford, as new industries began to take shape (see below). The priory was destroyed in 1538 as part of the Dissolution of the Monasteries and a new manor house constructed by King Henry VIII. In 1576 Dartford Grammar School was founded, part of the Tudor emphasis on education for ordinary people.
Many Protestants were executed during the reigns of Queen Mary (1553–1554) and Philip and Mary (1554–1558), including Christopher Waid, a Dartford linen-weaver who was burnt at the stake in front of thousands of spectators on the Brent in 1555. The Martyrs Memorial on East Hill commemorates Waid and other Kentish Martyrs.
The earliest industries were those connected with agriculture, such as the brewing of traditional beers and ales. Lime-burning and chalk-mining also had their place. Fulling was another: the cleansing of wool needed a great deal of water, which the river could provide. This led to other water-based industries, using hydropower to operate machinery.
Sir John Spilman set up the first paper mill in England at Dartford in 1588 on a site near Powder Mill Lane, and soon some 600 employees worked there, providing an invaluable source of local employment. Iron-making on the Weald was in full operation at this time, and iron ingots were sent to Dartford, to England's first iron-slitting mill, set up by the Darent at Dartford Creek in 1595 by Godfrey Box, an immigrant from the Low Countries. In 1785, a blacksmith from Lowfield Street began to make engines, boilers and machinery. Some of that machinery was for the local gunpowder factory run by Miles Peter Andrews and the Pigou family. In 1785, the firm of J & E Hall was set up, specialising in heavy engineering, and later refrigerating equipment, and, by 1906, vehicle production.
From those beginnings in the 18th century was to come the industrial base on which the growth and prosperity of Dartford were founded.
In 1840 the mustard factory of Saunders & Harrison was described as being 'perhaps the largest in the kingdom'. Dartford Paper Mills were built in 1862, when excise duty on paper was abolished. Between 1844-1939 the fabric printing works of Augustus Applegath were in being in Bullace Lane: again a firm using the waters of the river.
The demand created by World War I meant that output at the local Vickers factory multiplied, with a positive effect on the local economy. Burroughs-Wellcome chemical works (later incorporated into GlaxoSmithKline) made Dartford a centre for the pharmaceutical industry. During the war, many Belgian refugees arrived in the town. Unable to accommodate them all, many people were housed with volunteers.
The Mazda motor manufacturer has its UK head office at the large Thames-side Crossways Business Park.
In early 2006, the since-closed South East England Development Agency (SEEDA) purchased the former Unwins (an off-licence chain that went into administration in 2005) depot on the edge of the town. The warehouse was demolished and a business centre, The Base built in its place. The Base will be managed by Basepoint Centres and funded by the non-departmental public body, HCA.
The former GlaxoSmithKline manufacturing site in Mill Pond Road was bought by an off-shore property trust in April 2010. Essential Land has ambitious plans to construct 1,050 homes, in addition to offices, shops and restaurants. The first phase of the £150 million development could be complete as early as 2014.