Knebworth is a village and civil parish in the north of Hertfordshire, England, immediately south of Stevenage. The civil parish covers an area between the villages of Datchworth, Woolmer Green, Codicote, Kimpton, Whitwell, St Paul's Walden and Langley, and encompasses the village of Knebworth, the small village of Old Knebworth and Knebworth House.

There is evidence of people living in the area as far back as the 11th century as it is mentioned in the Domesday Book of 1086 where it is referred to as Chenepeworde with a recorded population of 33 households and land belonging to Eskil (of Ware), a thegn of King Edward the Confessor. The name 'Knebworth' may mean either the farm belonging to the 5th century Saxon Dane, Cnebba, or simply There is an alternative interpretation, though, that the name could instead have meant 'village on the hill'. The spelling of the name 'Chenepeworde' has since changed to become the modern spelling of 'Knebworth'.

The original village, now known as Old Knebworth, developed within the parish of the Church of St Mary and St Thomas. The stone church was built around 1120, and although the Domesday Book makes no mention of the church there is speculation to suggest there may have been a Saxon church of timber on the site before the more substantial one was built.

The manor passed into the hands of the Lytton family around 1492, when the manor house was rebuilt to a Late Gothic manor house. The house changed very little until the 19th century when it was re-modelled into the present-day Tudor Gothic building.

Knebworth was a largely agricultural community, producing wheat and barley in particular. The proximity to London via the Great North Road (subsequently the A1, and now the B197 since the opening of the A1(M) motorway in 1962) made it possible to transport produce.

By the start of the 19th century, Knebworth had a population of around 250 people, but the Industrial Revolution and the railway coming to Knebworth changed that. Initial development of the newer Knebworth village was centred a mile to the east of Old Knebworth on the area around the new railway station and the Great North Road. The route of the railway – which was originally meant to go through Codicote to the west – was negotiated by Lord Lytton so that it would go through the grounds of Knebworth, and have a station built there.  The Great Northern Railway, itself opened in 1850, opened a station at Knebworth in 1884. The station created a brand-new settlement called Knebworth Station – known later as New Knebworth, and later still, just as Knebworth – with the original village becoming known as Old Knebworth. Lord Lytton set up a company, Knebworth Garden Villages, to build homes either side of the railway embankment. Prior to this, only a few farmhouses had stood nearby, including Swangley's farm and Deards End farm. The station site eventually grew to include a signal box and goods yard to the north, approximately where Kerr Close is now.

Migrants from London, neighbouring counties, and even more distant areas of the country came to work in the new settlement.

At the turn of the century the architect Edwin Lutyens built Homewood, south-east of Old Knebworth, as a dower house for Edith Bulwer-Lytton. Her daughter, the suffragette Constance Lytton, also lived there, until just before her death in 1923. Edith's third daughter, Lady Emily Bulwer-Lytton, had married Lutyens in 1897. Lutyens was responsible for a number of notable buildings in the new village of Knebworth as well, including the Bank, St Martin's church, the Golf Clubhouse and the telephone exchange.