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. Between the Dyke and Newmarket lies the Heath, renowned as the earliest English race-course. This form of amusement seems to have come in with the Stuart Dynasty. James the First is said to have inaugurated the sport. But the well-known tale of how Edward the First escaped from his captivity at Hereford, by inducing his guards to ride matches till their horses were exhausted and then galloping off on his own fresh mount, shows that the idea was afloat long before. And at Newmarket in particular such matches must often have been ridden in connection with the great horse mart which has given the town its name. This New Market is, like the New Forest, now far from new. It dates from the year 1227, when a frightful outbreak of sickness frightened away buyers and sellers from their older market-place two miles off at Exning (a pretty natural amphitheatre of turf bright with many springs), and sent them to meet for the future in the freer air of the Heath. This word, by the way, does not, in Cambridgeshire, imply the existence of heather, merely meaning an open space.