The first mention of Barstable (Berdestapia) a name associated with Basildon in the *Domesday Book. Berlesduna (Basildon), Dantuna (Dunton), Leiendunã (Laindon), Langenduna (Langdon), Leam (Lee Chapel), Nezendena (Nevendon), Piceseia (Pitsea) and Phenge (Vange), are also recorded in the book as belonging to the Barstable Hundred. All names are believed to be of Saxon origin dating from the Anglo-Saxon occupation of south east England, from the mid 5th century AD to the Norman conquest of 1066.

*The Domesday Book is a record of the great survey carried out over most of England and parts of Wales as commissioned by William I, also known as William the Conqueror (circa 1028 – 9 September 1087) to determine who owned what. It was begun in 1085 and completed in 1086 and written in Latin.

All Saints Church in Vange built. The present church in London Road although much changed through the centuries in part dates back to the 12th century. It is believed to be the oldest existing building in Basildon. A new Anglican church to serve Vange, St. Chad's, was later built and opened in 1958 in Timberlog Lane (now Clay Hill Road) and services at All Saints went into a gradual decline. Eventually the church was closed and made redundant in 1996. The church has been recognised by English Heritage as having special importance and is now a Grade II listed building. It is currently in the care of the Church Conservation Trust.

The parish church of St. Nicholas in Laindon is known to have existed. The exact details as to the dates on which the church is said to have been built remain unclear but one aspect of the church, notably the nave, is said to date from this period. The present building, if some accounts are to be believed, dates from 1326. The south aisle and chancel were added sometime in the 14th century so this date might have some foundation. A small two storey annexe at the west end, used as a Priests House, was another later addition, possibly in the 17th century or earlier. This became Puckle's School from around 1837. The Schoolmaster James Hornsby taught there for 48 years. In 1883 a restoration was carried out by then rector John Mathias Proctor. St. Nicholas Church is currently the only building within the town of Basildon to have Grade 1 listed status.

Richard de List is the first recorded rector of St. Nicholas Church in Laindon.

The family of Hugh le Crane are said to be the first to farm the area. The farm and lands stood in Nevendon until the late 1950s, being known for much of that time as either Cranes or Great Spenders. It was last occupied by the McCheyne family when it was purchased, along with a substantial portion of land, by Basildon Development Corporation as the site of the new towns first industrial estate. The Crane name is remembered in the road names Cranes Farm Road, Cranes Lane, Cranes Court and Cranes Close. The industrial estate, originally called No.1, was also later renamed Cranes.

The Essex parliamentary constituency created. The constituency survived until 1832 when North Essex and South Essex divisions were created.

30th May

The Peasants' Revolt. The uprising occurred when a large group of rebel villagers from Fobbing, Corringham and Stanford along with other settlements, said to include Langdon Hills and Laindon, marched on Brentwood to complain about the poll tax. They were seeking a reduction of taxation and hoped to convince the King's tax collector for Essex, Thomas Bampton, to see fit to inform the King of their demands. A battle then ensued and Bampton was chased out of Brentwood. Word spread to Kent of the uprising and another large group of rebels, led by Walter "Wat" Tyler, set off from Canterbury to London to meet with the Essex rebels and seek an audience with King Richard II. Although Tyler did eventually meet with the King and some negotiation took place, at a further meeting on 15th June at Smithfield, Tyler was stabbed and killed, allegedly by the mayor of London, William Walworth and other servants of the King. Although other revolts continued, including one at Billericay, the rebels were soon defeated and more than a thousand of them were put to death on orders of the King. The revolt is remembered locally, where at Pitsea in 1984, a large country park was opened by Basildon Council who named it Wat Tyler, in honour of the rebel leader.

22nd July

The former parish of Westley or West Lee is united with Langdon Hills parish. The residential development and green at Eastley on the Lee Chapel South estate was so named as it lies to the east of Lee Chapel.