The insurrection was in appearance an exceedingly dangerous one. Almost every Norman baron in England revolted and carried his vassals with him. Odo, Bishop of Bayeux, the king's uncle, was the prime mover in the affair. He had been released from his prison by the Conqueror on his death-bed, and had been restored by William II to his earldom of Kent; but his hope of becoming the chief counsellor of the king, as he had become of Robert in Normandy, was disappointed. With him was his brother, Robert of Cornwall, Count of Mortain. The other great baron-bishop of the Conquest, Geoffrey of Coutances, was also in insurrection, and with him his nephew, Robert of Mowbray, Earl of Northumberland. Another leading rebel was Roger, Earl of Shrewsbury, with his three sons, the chief of whom, Robert of Bellême, was sent over from Normandy by Duke Robert, with Eustace of Boulogne, to aid the insurrection in England until he should himself be able to cross the channel. The treason of one man, William of St. Calais, Bishop of Durham, was regarded by the English writers as particularly heinous, if indeed we are right in referring their words to him and not to Bishop Odo; it is at least evident from the sequel that the king regarded his conduct in that light. The reason is not altogether clear, unless it be that the position of greatest influence in England, which Bishop Odo had desired in vain, had been given him by the king. Other familiar names must be added to these: William of Eu, Roger of Lacy, Ralph of Mortimer, Roger Bigod, Hugh of Grantmesnil. On the king's side there were few Norman names to equal these: Hugh of Avranches, Earl of Chester, William of Warenne, and of course the vassals of the great Archbishop Lanfranc. But the real strength of the king was not derived from the baronial elements. The castles in most of the great towns remained faithful, and so did nearly all the bishops and the Church as a whole. But the weight which turned the scale and gave the decision to the king, was the support of the great mass of the nation, of the English as opposed to the Norman.