There were a variety of cultures, each with its own language. The Stone Age lasted in England until 2,000 BC, although some stone weapons were still used at the Battle of Hastings. Eventually they gave way to bronze implements and these were finally displaced by iron in 500-600 BC.
There are no data about the language used in the Paleolithic era. The first people in England whose language we have knowledge about are the Celts. Then Latin, introduced when Britain was a province of the Roman Empire, was spoken extensively for 4 centuries.
Fig.: Implements found in Huntingdonshire.
In the summer of 55BC, julius Caesar invades England to discourage the Celts from coming from Britain through the channel to assist the Celts in Gaul. The expedition was an utter disaster. Finally, the Roman Conquest took place in AD 43, conducted by Emperor Claudius, who sent an army of 40,000 to Britain and subjugated it in 3 years. The Celt uprising lead by Boudica in AD 61 did not deter them, and the Northern frontier advanced to Solway-Tyne, where they built a stone wall.
The Romans built highways, roads, military and civil centers, houses, baths, temples, theatres, heating and water supply systems, created beautiful mosaics and painted stucco, brought their own fashion in dresses and ornaments, and made pottery, glassware and other utensils. The Romanization was cut short in the 5th century.
Fig.: Roman pottery.
There is evidence of the use of Latin in inscriptions. It did not replace Celtic (as it did in Gaul) though. The use of Latin declined after the legions withdrew in 410.
In 449 there is another invasion, this time by Germanic tribes. For 100 years, bands from Denmark and the Low Countries invaded the South and East of the island. Jutes and Angles (Denmark), Frisians and Saxons (Germany) came in waves through the years and established themselves in different sites. The Picts and Scots, natives in the islands had remained unconquered and kept their own culture throughout the Romanization. The Celts depended on Roman arms when they withdrew from the island, and reached an agreement with the Jutes in order to lead the Picts and Scots out.
The Jutes settled in Kent, the Saxons in the South coast, Sussex, then Wessex too, Middlesex and North of the Thames, and the Angles at the North of the Humber.
The Celts were driven to the West (Wells, Cornwall) and the Roman towns were burned to the ground. It’s the beginning of the Anglo-Saxon civilization. Society is organized in clans and families and class distinctions are established: Eorls -hereditary aristocracy- and Ceorls -simple freemen-. They also established local assemblies called Moots, and administered justice through a system of fines, the Wergild, which varied according to the crime and the rank of the injured party.
The Anglo-Saxon Heptarchy is born:
Northumbria, Mercia, East Anglia, Kent, Sussex, Essex, and Wessex.