Accelerated Progress

The extent of West Saxon territory at the start of Ine's reign is fairly well known. The upper Thames valley on both sides of the river had long been the territory of the Gewisse, though Caedwalla had lost territory north of the river to the kingdom of Mercia before Ine's accession. To the west, Ceawlin of Wessex is known to have reached the Bristol Channel one hundred years before. The West Saxons had since expanded further down the southwestern peninsula, pushing back the boundary of the British kingdom of Dumnonia, which was probably roughly equivalent to modern Devon and Cornwall. On the West Saxons' eastern border was the kingdom of the East Saxons, which included London and what is now Surrey. To the Southeast were the South Saxons, on the coast east of the Isle of Wight. Beyond Sussex lay the kingdom of Kent. 

Wessex was an Anglo-Saxon kingdom in the south of Great Britain, from 519 until England was unified by Aethelstan in the early 10th century.

The Anglo-Saxons believed that Wessex was founded by Cerdic and Cynric, but this may be a legend. The two main sources for the history of Wessex are the Anglo-Saxon Chronicle and the West Saxon Genealogical Regnal List, which sometimes conflict. Wessex became a Christian kingdom after Cenwalh was baptized and was expanded under his rule. Caedwalla later conquered Sussex, Kent, and the Isle of Wight. His successor, Ine, issued one of the oldest surviving English law codes and established a second West Saxon bishopric. The throne subsequently passed to a series of kings with unknown genealogies.

During the 8th century, as the hegemony of Mercia grew, Wessex largely retained its independence. It was during this period that the system of shires was established. Under Egbert, Surrey, Sussex, Kent, Essex, and Mercia, along with parts Dumnonia, were conquered. He also obtained the overlordship of the Northumbrian king. However, Mercian independence was restored in 830. During the reign of his successor, Aethelwulf, a Danish army arrived in the Thames estuary but was decisively defeated. When Aethelwulf's son, Aethelbald, usurped the throne, the kingdom was divided to avoid war. Aethelwulf was succeeded in turn by his four sons, the youngest being Alfred the Great.

Wessex was invaded by the Danes in 871, and Alfred was compelled to pay them to leave. They returned in 876 but were forced to withdraw. In 878, they forced Alfred to flee to the Somerset levels but were eventually defeated at the Battle of Edington. During his reign, Alfred issued a new law code, gathered scholars to his court and was able to devote funds to building ships, organizing an army and establishing a system of burhs. Alfred's son, Edward, captured the eastern Midlands and East Anglia from the Danes and became ruler of Mercia in 918 upon the death of his sister, Aethelflaed. Edward's son, Aethelstan, conquered Northumbria in 927, and England became a unified kingdom for the first time. Cnut the Great, who conquered England in 1016, created the wealthy and powerful earldom of Wessex, but in 1066 Harold Godwinson reunited the earldom with the crown and Wessex ceased to exist.

Modern archaeologists use the term Wessex culture for a Middle Bronze Age culture from 1600 to 1200 BCE. A millennium before that, in the Late Neolithic, the ceremonial sites of Avebury and Stonehenge were completed on Salisbury Plain; but the final phase of Stonehenge was erected in the Wessex culture phase, early in the Bronze Age. This area has many other earthworks and erected stone monuments from the Neolithic and Early Bronze periods, including the Dorset Cursus, and earthwork that was oriented to the midwinter sunset. Although agriculture and hunting were pursued during this long period, there is little archaeological evidence of human settlements. From the Neolithic onward the chalk downland of Wessex was traversed by the Harrow Way, which can still be traced from Marazion in Cornwall to the coast of the English Channel near Dover, and was probably connected with the ancient tin trade.

During the Roman occupation, numerous country villas with attached farms were established across Wessex, along with the important towns of Dorchester and Winchester. The Romans, or rather the Romano-British, built another major road that integrated Wessex, running eastwards from Exeter through Dorchester to Winchester and Silchester and on to London. The early 4th century CE was a peaceful time in Roman Britain. However, following a previous incursion in 360 that was stopped by Roman forces, the Picts and Scots attacked Hadrian's Wall in the far north in 367 and defeated the soldiers stationed along it. They devastated many parts of Britain and laid siege to London. The Romans responded promptly, and Count Theodosius had recovered the land up to the Wall by 368.

The Romans temporarily ceased to rule Britain on the death of Magnus Maximus in 388. Stilicho attempted to restore Roman authority in the late 390s, but in 401 he took Roman troops from Britain to fight the Goths. Two subsequent Roman rulers of Britain, appointed by the remaining troops, were murdered. Constantine III became ruler, but he then left for Gaul and withdrew more troops. The Britons then requested assistances from Honorius, but when he replied in 410, he told them to manage their own defenses. By this point, there were no longer Roman troops in Britain. The Economic decline occurred after these events; circulation of Roman coins ended and the importation of items from the Roman Empire stopped.

In an Introduction to Anglo-Saxon England, Peter Hunter Blair divides the traditions concerning the Anglo-Saxon settlement of Britain into two categories: Welsh and English. After the Romans left, the Britons managed for a time without any major disruptions. However, when finally faced with northern invaders, they requested assistance from the Saxons in exchange for land. The were no conflicts between the British and the Saxons for a time, but following a dispute about the supply of provisions, the Saxons went to war against the British and severely damaged parts of the country. In, however, some Saxon troops left Britain, under Ambrosius Aurelianus, the British subsequently defeated those who remained. A lengthy conflict ensued, in which neither side gained any decisive advantage until the Britons routed the Saxons at the Battle of Mons Badonicus. After this, there occurred a peace period for the Britons.