King Henry was released and replaced on the throne, and for six months Warwick ruled England as his lieutenant. But there was bitterness and mistrust between the old Lancastrian faction and the Nevilles, and Queen Margaret refused to cross to England or to trust her son in the king-maker's hands. Her partisans doubted his sincerity, while many of the Yorkists who had hitherto followed Warwick in blind admiration found it impossible to reconcile themselves to the new régime. The duke of Clarence in particular, discontented at the triumph of Lancaster, betrayed his father-in-law, and opened secret negotiations with his exiled brother. Encouraged by the news of the dissensions among his enemies, Edward IV. resolved to try his fortune once more, and landed near Hull on the 15th of March 1471 with a body of mercenaries lent him by the duke of Burgundy. The campaign that followed was most creditable to Edward's generalship, but must have been fatal to him if Warwick had been honestly supported by his lieutenants. But the duke of Clarence betrayed to his brother the army which he had gathered in King Henry's name, and many of the Lancastrians were slow to join the earl, from their distrust of his loyalty. Edward, dashing through the midst of the slowly gathering levies of his opponents, seized London, and two days later defeated and slew Warwick at the battle of Barnet (April 13, 1471). Battle of Tewkesbury. Death of Edward, prince of Wales. Capture of Queen Margaret and murder of Henry VI. On that same day Queen Margaret and her son landed at Weymouth, only to hear that the earl was dead and his army scattered. But she refused to consider the struggle ended, and gathered the Lancastrians of the west for a final rally. On the fatal day of Tewkesbury (May 3, 1471) her army was beaten, her son was slain in the flight, and the greater part of her chief captains were taken prisoner. She herself was captured next day. The victorious Edward sent to the block the last Beaufort duke of Somerset, and nearly all the other captains of rank, whether Lancastrians or followers of Warwick. He then moved to London, which was being threatened by Kentish levies raised in Warwick's name, delivered the city, and next day caused the unhappy Henry VI. to be murdered in the Tower (May 21, 1471). Edward IV.