In prehistoric times Britain was joined to the rest of the continent. The first human inhabitants of Britain, and many of its animal inhabitants, came there over dry land.

Towards the end of the Ice Age the mighty prehistoric river, which joined the present-day Thames with the Rhine, overwhelmed the land joining Britain to the Continent and formed the present English Channel. In the period immediately after its formation the Channel was too stormy and full of strong currents to allow access to Britain by the nearest overseas route. The hunters of the Neolithic Age (New Stone Age) crossed the sea to Britain to the west of the Channel and settled along the western shores in their search for food. They found a country practically covered with virgin forest of oak and ash and swamps, except where the higher ground of the hills rose above the forest.

The first inhabitants of the island for whom a traditional name exists are the Iberians or Megalithic men, who probably form the basis of the present-day population in Western England, Wales, North and Western Scotland and Ireland. This race is supposed to have arrived in Britain from the region of the Mediterranean and inhabited it between 3000 and 2000 BC.

Soon after 2000 BC a new race of Apline stock came from the east of Europe. They entered the country, this time from the south-east and east. From their characteristic pottery found in their graves they are known as the Beaker Folk.

The race was certainly familiar with the use and working of bronze. The two peoples were closely related in culture and the newcomers spread along the east coast. Although a certain level of civilization was reached in the Early and Middle Bronze Ages, it was spread over only a small part of Britain. The ancient people, who gradually merged together, left behind impressive monuments, connected with religious rites at Stonehenge, Avebury and other sites. The name ‘Stonehenge’ comes from the old English ‘hengan’, meaning hanging stones. Stonehenge also served as an ancient observatory.

Soon after 700 BC Britain was invaded by the Celts, who are supposed to have come from Central Europe. A commonly accepted theory of their invasions is that they came in three distinct waves. The first group was called the Goidels or Gaels. These first Celts were driven by later invaders into the less fertile and more mountainous western and northern regions. The original language of Ireland and of North-West Scotland is thus Goidelic Celtic (Gaelic). The second wave of Celtic tribes, the Brythonic Celts or Brythons, from whose name is derived the word Britain, arrived in England between 600 and 500 BC and settled in the South of England, in Wales and in North-West England and South-West Scotland. Their language developed into the Celtic language of modern Wales.

A third wave of invaders, Belgae from Northern Gaul, containing many people of Teutonic origin, arrived about 100 BC and occupied the greater part of what are now known as the Home Counties (the central part of Great Britain).

The earliest Celts were in the bronze stage of development, but later Celtic invaders brought with them a knowledge of iron working. Trade, industry and agriculture flourished, as did sheep and cattle raising. The tribal form of government prevailed.