The fabric of the Roman law indeed never took root in England, but it is impossible not to recognize the result of the influence of the Roman missionaries in the fact that the codes of customary English law began to be put into writing soon after their arrival.
As yet these great results were still distant; a year passed before aethelberht yielded, and though after his conversion thousands of the Kentish men crowded to baptism, it was years before he ventured to urge the under-kings of Essex and East Anglia to receive the creed of their overlord. This effort of aethelberht however only heralded a revolution which broke the power of Kent for ever. The tribes of Mid-Britain revolted against his supremacy, and gathered under the overlordship of Raedwald of East Anglia. The revolution clearly marked the change which had passed over Britain. Instead of a chaos of isolated peoples, the conquerors were now in fact gathered into three great groups. The Engle kingdom of the north reached from the Humber to the Forth. The southern kingdom of the West-Saxons stretched from Watling Street to the Channel. And between these was roughly sketched out the great kingdom of Mid-Britain, which, however its limits might vary, retained a substantial identity from the time of aethelberht till the final fall of the Mercian kings.
For the next two hundred years the history of England lies in the struggle of Northumbrian, Mercian, and West-Saxon kings to establish their supremacy over the general mass of Englishmen, and unite them in a single England.
In this struggle the lead was at once taken by Northumbria, which was rising into a power that set all rivalry at defiance. Under aethel-frith, who had followed aethelric in 593, the work of conquest went on rapidly. In 603 the forces of the northern Britons were annihilated in a great battle at Daegsastan, and the rule of Northumbria was established from the Humber to the Forth. Along the west of Britain there stretched the unconquered kingdoms of Strathclyde and Cumbria, which extended from the river Clyde to the Dee, and the smaller British states which occupied what we now call Wales. Chester formed the link between these two bodies; and it was Chester that aethelfrith chose in 613 for his next point of attack. Some miles from the city two thousand monks were gathered in the monastery of Bangor, and after imploring in a three days' fast the help of Heaven for their country, a crowd of these ascetics followed the British army to the field. aethelfrith watched the wild gestures and outstretched arms of the strange company as it stood apart, intent upon prayer, and took the monks for enchanters. "Bear they arms or no," said the king, "they war against us when they cry against us to their God," and in the surprise and rout which followed the monks were the first to fall.
The British kingdoms were now utterly parted from one another. By their victory at Deorham the West-Saxons had cut off the Britons of Devon and Cornwall from the general body of their race. By his victory at Chester aethelfrith broke this body again into two several parts, by parting the Britons of Wales from those of Cumbria and Strathclyde. From this time the warfare of Briton and Englishman died down into a warfare of separate English kingdoms against separate British kingdoms, of Northumbria against Cumbria and Strathclyde, of Mercia against modern Wales, of Wessex against the tract of British country from Mendip to the Land's End. Nor was the victory of Chester of less importance to England itself. With it aethelfrith was at once drawn to new dreams of ambition as he looked across his southern border, where Raedwald of East Anglia was drawing the peoples of Mid-Britain under his overlordship.
The inevitable struggle between East Anglia and Northumbria seemed for a time averted by the sudden death of aethelfrith. Marching in 617 against Raedwald, who had sheltered Eadwine, an exile from the Northumbrian kingdom, he perished in a defeat at the river Idle. Eadwine mounted the Northumbrian throne on the fall of his enemy, and carried on the work of government with an energy as ceaseless as that of aethelfrith himself. His victories over Pict and Briton were followed by the winning of lordship over the English of Mid-Britain; Kent was bound to him in close political alliance; and the English conquerors of the south, the people of the West-Saxons, alone remained independent. But revolt and slaughter had fatally broken the power of the West-Saxons when the Northumbrians attacked them. A story preserved by Baeda tells something of the fierceness of the struggle which ended in the subjection of the south to the overlordship of Northumbria. Eadwine gave audience in an Easter court which he held in a king's town near the river Derwent to Eumer, an envoy of Wessex, who brought a message from its king. In the midst of the conference the envoy started to his feet, drew a dagger from his robe, and rushed madly on the Northumbrian sovereign.
Lilla, one of the king's war-band, threw himself between Eadwine and his assassin; but so furious was the stroke that even through Lilla's body the dagger still reached its aim. The king however recovered from his wound to march on the West-Saxons; he slew and subdued all who had conspired against him. and returned victorious to his own country. The greatness of Northumbria now reached its height. Within his own dominions Eadwine displayed a genius for civil government which shows how completely the mere age of conquest had passed away. With him began the English proverb so often applied to after kings, "A woman with her babe might walk scatheless from sea to sea in Eadwine's day." Peaceful communication revived along the deserted highways; the springs by the roadside were marked with stakes, and a cup of brass set beside each for the traveller's refreshment. Some faint traditions of the Roman past may have Hung their glory round this new "Empire of the English;" some of its majesty had at any rate come back with its long-lost peace. A royal standard of purple and gold floated before Eadwine as he rode through the villages; a feather-tuft attached to a spear, the Roman tufa, preceded him as he walked through the streets.