Meanwhile the old southland homes of the unhappy Britons were being shared up by their English exterminators. The East Anglians swarmed over the uplands to the east, and joined hands (not in friendship) with the more powerful Mercians swarming in from the west. Roughly speaking the Cam divided these jarring tribes, which lived in undying hostility till the various English Kingdoms were united into one (in A.D. 827) by the genius and valour of Egbert, the first "King of the English." But the boundaries were not effaced till the desolating flood of the Danish invasions poured over all.

When that flood was stayed by Egbert's glorious grandson, Alfred the Great, and the district once more made English and Christian by his only less glorious son, Edward "the Elder," it was formed by him into a County called, from its chief town, Cambridgeshire (or, as it was then, "Granta-bryg-shire"). This was in the year 921. But for the first idea of any union between this new County and the old Isle of Ely we must wait another two centuries, when, in 1107, the Abbot of Ely became a Bishop, with the Isle and the County together for his See. The ecclesiastical tie thus formed has gradually developed into a civil tie also; just as the first union of the English race under a common Primate, the Archbishop of Canterbury, paved the way for its union under a common King.

To many charming byways amid the streamlets and the meadows and the gentle slopes of this southern Cambridgeshire the seven highways out of Cambridge will successively conduct us. The highways themselves are, as has been said, seldom inspiring thoroughfares, save for their far-flung horizons; and the Newmarket Road least of all, for it is, as might be looked for, motor-swept beyond all the rest. The one near-hand object alone worth mention is the little Church of Quy, whose far-seen tower dominates some miles of the road. But this has little interest except its curious name, which is matter of dispute amongst etymologists. "Cow-ey" is the most commonly accepted derivation, meaning the Island of Cows. But Quy can never have been an island. More probably it is "Cow-way," like the "Cowey Stakes" on the Thames, signifying that here was a passage for cattle across the marshy ground which bordered the little stream crossed by the road before reaching the church. This stream flows out of Fulbourn Fen, an isolated patch of fen-land a mile square, even yet only half reclaimed, and of old so impassable that it determined the line of the great Fleam Dyke, which runs up to it on either side but does not need to cross it.

Quy Church.

The Fleam Dyke is one of the great prehistoric lines of defence which were run from the Fens of the Cam to the summit of the East Anglian heights. Those heights were in ancient times clothed with dense forest, and formed an impenetrable barrier against enemies from the west seeking to invade the East Anglian districts. So too did the morasses of the fenland. But between fen and forest stretched a strip of open grassland furnishing easy access. To defend this, the only gate into their territory, was the great object of the inhabitants of those districts; and they ran across it two stupendous earthworks, the Fleam Dyke as their outer bulwark and the Devil's Dyke, which we meet at Newmarket, as the inner.[124] The former stretches for a length of some ten miles from the banks of the Cam at Fen Ditton to the uplands by Balsham (its course broken by Fulbourn Fen); the latter ranges in a long unbroken rampart from the Fen at Reach to Wood Ditton (i.e. "the ditch-end in the forest").

When these were constructed we do not know. They first appear in history as the scene of desperate fighting between Britons and Romans in the first century of our era. But they may very probably have existed before even the Britons came into the land. Magnificent earthworks they are, some 10 feet high on the inner side, and on the outer at least 30, from the bottom of the great ditch which flanks them to the crown of the parapet. When that parapet was topped by a palisade of timber, they must have presented formidable obstacles indeed. The Fleam Dyke we do not see from this road. But as we approach Newmarket, and enter upon its famous Heath, we cross the Devil's Dyke; and, as we look at its mighty dimensions, we cease to wonder that our simple-minded ancestors should have ascribed its formation to superhuman agency.

The gap by which we pass through the Devil's Dyke deserves notice. It is the one gap in the whole line of the work, and was left to admit, not our road, but that which we now join, the London Road of Newmarket. For this is one of the most venerable tracks in the land, being the "Icknield Way," made how long ago Heaven only knows. From the very first settlement of the country there must always have existed some route along this open strip between fen and forest which formed the only line of communication from the eastern to the midland regions of our island. In British days the former were occupied by the great clan of the Iceni, whose name survives in the English appellation of the road, and can be traced in many place-names along it, such as Ickleton in Cambridgeshire, and Ickleford in Hertfordshire.[125] The road followed the western slope of the chalk hills to the Thames and beyond, till it tapped the line of the great Tin-road, by which that then precious metal was brought from Cornwall to Thanet.[126]

At the Roman conquest of Britain in 55 A.D. the Iceni were friendly to the invaders, whom indeed they had invited into the land, to free them from their subjection to the House of Cymbeline, King of Britain. But when, a few years later, during the settlement of the country, the Roman general Ostorius ordered them to give up their arms, they regarded the demand as an intolerable insult, and bade him defiance, manning the Fleam Dyke against him. But such was his energy that, though he had no regular troops with him, his light-armed auxiliaries stormed the whole length of the line at a single rush. The routed Icenians fled in panic homewards, only to find their way hopelessly barred by their own fortifications along the Devil's Dyke, and all but the few who could force their way through the mad crush at this one narrow gap, were, in spite of a desperate resistance, slaughtered wholesale. The tribe were then disarmed, and endured unresistingly the licence and greed of Roman officials and Roman moneylenders, till goaded into madness, twelve years later, by the wrongs of their "warrior-queen," Boadicea. Then followed that convulsive explosion of popular rage and despair, in which every Roman within reach was massacred with every circumstance of horror, and to which the Romans, after their victory, replied by such a policy of extermination as to blot the Icenian name from the page of history. Never again do we meet with it.