Until the late 9th century AD, England did not exist as a single political entity. The country was divided into many kingdoms. As certain kingdoms grew stronger they seized land from the weaker ones. By 800, power was divided between just five kingdoms: Northumbria, Mercia, Wessex, Kent, and East Anglia. However, in 865 the Great Army of the Danes invaded and overran all the Anglo-Saxon kingdoms apart from Wessex.

After Alfred, king of Wessex (reigned 871-99) won a decisive battle against the Danes he brokered a peace which guaranteed that they would remain inside an area to be known as the Danelaw. This left half the country free from Danish rule and according to the 9th-century Anglo-Saxon Chronicle, in 886 everyone living there submitted to Alfred as their leader. However, Alfred was not king of England as we think of it, because half the country belonged to the Danes. Over the following decades, Alfred’s successors won back much of this territory. Although some of the larger kingdoms were not easily integrated, the idea of ‘England’, rather than regional kingdoms, began at this time. Finally, in 925, Athelstan, grandson of Alfred, was crowned the first king of the English. He ruled over all the English peoples, including those who had been living in the Danelaw.