Anglo-Saxon Britain by Grant Allen

We can now picture to ourselves the general aspect of the country after the English colonies had established themselves as far west as the Somersetshire marshes, the Severn, and the Dee. The whole land was occupied by little groups of Teutonic settlers, each isolated by the mark within their own township; each tilling the ground with their own hands and those of their Welsh serfs. The townships were rudely gathered together into petty chieftainships; and these chieftainships tended gradually to aggregate into larger kingdoms, which finally merged in the three great historical divisions of Northumbria, Mercia, and Wessex; divisions that survive to our own time as the North, the Midlands, and the South. Meanwhile, most of the Roman towns were slowly depopulated and fell into disrepair, so that a "waste chester" becomes a common object in Anglo-Saxon history. Towns belong to a higher civilisation, and had little place in agricultural England.

The roads were neglected for want of commerce; and trade only survived in London and along the coast of Kent, where the discovery of Frankish coins proves the existence of intercourse with the Teutonic kingdom of Neustria, which had grown up on the ruins of northern Gaul. Everywhere in Britain the Roman civilisation fell into abeyance: in improved agriculture alone did any notable relic of its existence remain. The century and a half between the conquest and the arrival of Augustine is a dreary period of unmixed barbarism and perpetual anarchy.