A very brief history of how England began
Before the Romans, mainland Britain was made up of regional tribes. Map and guide to pre Roman tribes.
While the land was unified to an extent by the Romans, it was still just a province within the empire without its own identity. While the area now covered by England and Wales was designated 'Britanica', it was a relatively small part of the empire and certainly not autonomous. Map of Roman Empire
After the Romans left, the Angles, Saxons and Jutes landed and carved the territory up over the next couple of hundred years. By 600, the Britons had been pushed back to what is now Cornwall, Wales and North West of England/West of Scotland.
Around 600 AD
In time, a loose federation developed, now known as the Heptarchy; the seven Kingdoms. The names of the Kingdoms reflected the dominance of the Saxons and the Angles
Map of the Heptarchy
This interesting map shows the Saxon influence with Wessex and East Saxons (now Essex) and the Angles with East Anglia and Mercia under the 'Middle Angles'.
In time Wessex and Mercia emerged as the two most powerful Kingdoms, leading the rivalry between Saxons and Angles respectively. Kent and Northumbria were independent Kingdoms, although Kent seems to have been closely attached to Wessex. But there was no concept of 'England' by this time. It is also interesting see how rivers were the main basis for boundaries and also some similarity with those pre Roman tribes - yet also some of the roots of today's regional identities....
The period from about 800 onwards was the dawn of a country. Egbert became a king of Wessex in 802 Egbert and in effect the beginning of the royal line which can be traced (albeit with some elaborate twists and turns - and far from a direct line!) to the current Queen. Egbert's roots are disputed, but his descent from Cerdic Cerdic is indicated in the Wessex family tree Wessex from Cerdic.
Having beaten Mercia in battle, Egbert has a claim to having been the first ruler of much of what we now call England, but this was not sustained. His son Athelwulf had four son, all of whom became rulers - the last being Alfred the Great. Alfred the Great. By now, the enemy was the Vikings, whose powerbase was Northumbria and the Northern and Eastern side of the land in general. Alfred did not unify the country, although the dream of 'England' (Englaland - land of the Angles) took root around this time - with a focus on Christianity and repelling (or integrating) the Danes [A question I have not resolved is why it was called "the land of the Angles", since it seems fairly clear that the Saxons - and Wessex in particular - were in charge; why did we not become Saxonland or similar?].
Alfred's daughter Athelflead Aethelflaed - the Lady of the Mercians, seems to have been an important and interesting character in the Wessex dynasty.
A degree of unification of Wessex (Saxon) and Mercian (Angle) interests appears to be her sponsorship of Alfred the Great's grandson Athelstan. So in the four generations of the Wessex dynasty from Egbert to Athelstan, arguably the dream of an 'England' was created and the turned into a reality - with the big meeting at Eamont Bridge being perhaps the formal beginning.
After Athelstan, the House of Wessex had a turbulent time over the next century or so - with nine monarchs, interupted by Danish rulers between 1016 to 1042, up to the Norman Conquest. Full list of monarchs of England. Arguably, the Wessex dynasty should have a place alongside the Plantaganets, Tudors or current Hanoverian line (which began with George 1st in 1714) in our history. Wessex rulers from 495 to 954
Certainly, by 1066, England was already a relatively cohesive - and prosperous - country, when William the Bastard (or 'Conquerer' as he is now known) - a Viking descendent - took it over. William the Conquerer. The Norman Conquest was definitely not the start of the nation of England - while it was an evolution and is open to debate, I suggest that the deal done in Cumbria on 12 July 927 had created the state we call England.