A Roman villa has been excavated just south of the village.

The town was probably part of the lands of the Abbey of St. Albans, although actual records have been lost.
At the Norman conquest the manor was given to William's half brother Robert, Count of Mortain who let it to one Ralf.
It is around the manor that the present village developed as a linear village lying on the old road from London to Berkhamsted and the Midlands of England.
In the Domesday Book of 1086, Langley was in the hundred of Danish.

Around 1276, the manor was purchased by Queen Eleanor and a palace was built on the hill above the village to its west with a deer park extending to its south.
This gave the village its link to royalty, first being renamed Langley Regina after its sponsoring queen, and then later changed to Langley Regis or later still by the added epithet "Kings".
The village remained the location of Kings Langley Palace, a royal palace of the Plantagenet kings of England: a Dominican priory was founded next to the palace and remains of this can still be seen.
The palace and the grand church that accompanied the priory fell into disrepair at the Dissolution of the Monasteries and little remains above ground level.

The Church of All Saints was built during the 14th century on the site of an earlier church.
The body of King Richard II was buried here for a time after his probable murder at Pontefract Castle in 1400.
It was later removed to Westminster Abbey.
The body of Edmund of Langley, died 1402, the fifth son of Edward III and the first Duke of York, still rests in the memorial chapel.

The 18th century Sparrows Herne turnpike road (later the A41 trunk road) traversed the Chilterns via the valley of the River Gade and ran down the village high street.
The 16th century Saracen's Head public house is a coaching inn which flourished in this period.

The Grand Union Canal dating from 1797, and the 1838, London and Birmingham Railway which later became the West Coast Main Line, (the main railway line from London to the north west) pass just east of the village at Kings Langley railway station.
There are many businesses located near the station in Home Park Industrial Estate which is also the site of the Construction and Engineering Centre of West Herts College.

20th century housing developments have led to the village spreading out on either side of the main road.
The A41 has now been diverted west of the village leaving the high street to local traffic for the first time in centuries.

During the Second World War, the village was home to the secret headquarters in Britain of the Polish Underground army based at Barnes Lodge just off the Hempstead Road near Rucklers Lane.

Kings Langley was the site of the factory making Ovaltine; the listed factory facade is now all that is left and still stands alongside the railway line among a new housing development.
The Ovaltine factory itself has been converted into a series of flats and duplexes.

The former Ovaltine Egg Farm was converted into energy-efficient offices which house Renewable Energy Systems.
The complex incorporates a highly visible 225 kW Vestas V29 wind turbine alongside the M25.

Kings Langley School is the local comprehensive school, situated on Love Lane to the west of the village.

Kings Langley is also the site of a Waldorf School, the Rudolf Steiner School Kings Langley.
This is built on the grounds of the old palace, of which only a small basement part of a pillar remains to be seen.
There is a small display cabinet of finds from the palace period in the school entrance foyer.

The village became twinned with Achiet-le-Grand in France in November 2009, in honour of Christopher Cox from the village who won a Victoria Cross in fighting near Achiet-le-Grand in the First World War.
A Roman villa has been excavated just south of the village.
The town was probably part of the lands of the Abbey of St. Albans, although actual records have been lost. At the Norman conquest the manor was given to William's half brother Robert, Count of Mortain who let it to one Ralf. It is around the manor that the present village developed as a linear village lying on the old road from London to Berkhamsted and the Midlands of England. In the Domesday Book of 1086, Langley was in the hundred of Danish.
Around 1276, the manor was purchased by Queen Eleanor and a palace was built on the hill above the village to its west with a deer park extending to its south. This gave the village its link to royalty, first being renamed Langley Regina after its sponsoring queen, and then later changed to Langley Regis or later still by the added epithet "Kings". The village remained the location of Kings Langley Palace, a royal palace of the Plantagenet kings of England: a Dominican priory was founded next to the palace and remains of this can still be seen. The palace and the grand church that accompanied the priory fell into disrepair at the Dissolution of the Monasteries and little remains above ground level.
The Church of All Saints was built during the 14th century on the site of an earlier church. The body of King Richard II was buried here for a time after his probable murder at Pontefract Castle in 1400. It was later removed to Westminster Abbey. The body of Edmund of Langley, died 1402, the fifth son of Edward III and the first Duke of York, still rests in the memorial chapel.
The 18th century Sparrows Herne turnpike road (later the A41 trunk road) traversed the Chilterns via the valley of the River Gade and ran down the village high street. The 16th century Saracen's Head public house is a coaching inn which flourished in this period.
The Grand Union Canal dating from 1797, and the 1838, London and Birmingham Railway which later became the West Coast Main Line, (the main railway line from London to the north west) pass just east of the village at Kings Langley railway station. There are many businesses located near the station in Home Park Industrial Estate which is also the site of the Construction and Engineering Centre of West Herts College.
20th century housing developments have led to the village spreading out on either side of the main road. The A41 has now been diverted west of the village leaving the high street to local traffic for the first time in centuries.
During the Second World War, the village was home to the secret headquarters in Britain of the Polish Underground army based at Barnes Lodge just off the Hempstead Road near Rucklers Lane.
Kings Langley was the site of the factory making Ovaltine; the listed factory facade is now all that is left and still stands alongside the railway line among a new housing development. The Ovaltine factory itself has been converted into a series of flats and duplexes.
The former Ovaltine Egg Farm was converted into energy-efficient offices which house Renewable Energy Systems. The complex incorporates a highly visible 225 kW Vestas V29 wind turbine alongside the M25.
Kings Langley School is the local comprehensive school, situated on Love Lane to the west of the village.
Kings Langley is also the site of a Waldorf School, the Rudolf Steiner School Kings Langley. This is built on the grounds of the old palace, of which only a small basement part of a pillar remains to be seen. There is a small display cabinet of finds from the palace period in the school entrance foyer.
The village became twinned with Achiet-le-Grand in France in November 2009, in honour of Christopher Cox from the village who won a Victoria Cross in fighting near Achiet-le-Grand in the First World War.
Kings Langley