The First People of Britain

For almost a million years, various species of humans have occupied Great Britain at different times.

At Happisburgh on the Norfolk coast, evidence of human occupation dates to around 900,000 years ago, where stone tools and footprints were probably made by an archaic human species, Homo antecessor.
The earliest evidence of human footprints outside of Africa, on the Norfolk Coast in the East of England
The oldest human fossils found at Boxgrove in Sussex, around 500,000 years old, are by Homo heidelbergensis.

A geological ridge running between the regions of the Weald in southern England and Artois in northern France, called the Weald-Artois Anticline, existed until around 425,000 years ago, when a megaflood broke through the ridge, and Britain became an island.

Fossils dating to around 400,000 years ago, of very early Neanderthals, have been found at Swanscombe in Kent.

About 225,000 year old fossils of classic Neanderthals have been found at Pontnewydd in Wales.
A DNA analysis of 50,000-year-old Neanderthal suggests that at least some of the ancient hominids probably had pale skin and red hair
Between 180,000 and 60,000 years ago, Britain seems to have been unoccupied, as no human remains or tools have been found.

60,000 years ago, Neanderthals returned. But, by 40,000 years ago, they had become extinct.

From 22,000 years ago, much of Europe was covered in ice. However, the ice age ended about 11,500 years, and since then, Britain has been continuously occupied.

Early Mesolithic hunter-gatherers lived on an area called Doggerland, a tract of now-submerged territory, until around 5600 BC.

At Star Carr in Yorkshire in northern England, deer skull masks, that may have been headdresses used by hunter-gatherers, have been found.
Star Carr collection at Yorkshire museum - mesolithic headdress made from deer skull.
By around 4000 BC, Britain was occupied by people with a Neolithic culture.

Migrants from around today's Greece and Turkey, bringing farming methods, replaced the indigenous hunter-gatherer population. 

Farming was practiced for up to 1000 years on the continent before it came to Britain.

The Beaker People (named after the inverted-bell beaker drinking vessel) came into Britain about 2500 B.C. They were farmers and archers and probably the first inhabitants of Britain to use woven fabrics. The most famous site in Britain from this period is Stonehenge.
A distinctive pottery drinking vessel found in Great Massingham, England, part of the "Beaker Culture"
It is believed that the Celts arrived in Britain about 1,000BC. Iron Age Britain was dominated by the Celts.

In 55 BC Julius Caesar's first invasion of Britain occurred, and this was the start of recorded history.

The Celts were often in conflict with the Romans. 

The end of Roman rule in Britain occurred when Magnus Maximus withdrew troops from northern and western Britain in 383 CE.

England changed from Romano-British to Germanic. The Celtic tribes are driven out to places like Cornwall and Wales. Many Hunter-Gatherers may have died from diseases to which they had no immunity.
Bede's World, Jarrow, UK. reconstructed Anglo-Saxon dwellings and farm
Neither the Romans nor the Anglo-Saxons were able to successfully invade Ireland. Most of modern Scotland was not incorporated into the Roman Empire. The Roman Empire occupied most of Wales.

According to DNA studies, fewer than one in 30 people in England can trace their origins to Britain’s first farmers. Evidence shows that an influx of people to southern England occurred about 3,000 years ago (the Late Bronze Age), of people descending from the early European farmers.