Warwick landed in the West Country on 13 September 1470, accompanied by Clarence and some unswerving Lancastrian nobles, including the Earl of Oxford and Jasper Tudor, the Earl of Pembroke. As Edward made his way south to face Warwick, he realised that Warwick's brother John, Marquess of Montagu, who had up till then remained loyal to Edward, had defected at the head of a large army in the North of England. Edward fled to King's Lynn where he took ship for Flanders, part of Burgundy, accompanied only by his youngest brother, Richard of Gloucester, and a few faithful adherents.

In London, Warwick released King Henry, led him in procession to Saint Paul's cathedral and installed him in Westminster palace. Warwick's position nevertheless remained precarious. His alliance with Louis of France and his intention to declare war on Burgundy was contrary to the interests of the merchants, as it threatened English trade with Flanders and the Netherlands. Clarence had long been excluded from Warwick's calculations. In November 1470, Parliament declared that Prince Edward and his descendants were Henry's heirs to the throne; Clarence would become King only if the Lancastrian line of succession failed. Unknown to Warwick, Clarence secretly became reconciled with his brother, King Edward.

With Warwick in power in England, it was Charles of Burgundy's turn to fear a hostile alliance of England and France. As an obvious counter to Warwick, he supplied Edward with money (50,000 florins), ships and several hundred men (including handgunners). Edward set sail from Flushing on 11 March 1471 with 36 ships and 1200 men. He touched briefly on the English coast at Cromer but found that the Duke of Norfolk, who might have supported him, was away from the area and that Warwick controlled that part of the country. Instead, his ships made for Ravenspurn, near the mouth of the River Humber, where Henry Bolingbroke had landed in 1399 on his way to reclaim the Duchy of Lancaster and ultimately depose Richard II.

Edward's landing was inauspicious at first; the ships were scattered by bad weather and his men landed in small detachments over a wide area on 14 March. The port of Kingston-upon-Hull refused to allow Edward to enter, so he made for York, claiming rather like Bolingbroke that he was seeking only the restoration of the Duchy of York. He then began to march south. Near Pontefract Castle he evaded the troops of Warwick's brother Montagu. By the time Edward reached the city of Warwick, he had gathered enough supporters to proclaim himself King again. The Earl of Warwick sent urgent requests for Queen Margaret, who was gathering fresh forces in France, to join him in England. He himself was at Coventry, preparing to bar Edward's way to London, while Montagu hastened up behind the King's army.

Edward however, knew that Clarence was ready to turn his coat once again and betray Warwick, his father-in-law. He marched rapidly west and joined with Clarence's men who were approaching from Gloucestershire. Clarence appealed to Warwick to surrender, but Warwick refused to even speak to him. Edward's army made rapidly for London, pursued by Warwick and Montagu. London was supposedly defended by the 4th Duke of Somerset, but he was absent and the city readily admitted Edward. The unfortunate and by now feeble Henry VI was sent back to the Tower of London. Edward then turned about to face Warwick's approaching army. On 14 April, they met at the Battle of Barnet. In a confused fight in thick fog, some of Warwick's army attacked each other by mistake and at the cries of "Treachery!" his army disintegrated and was routed. Montagu died in the battle, and Warwick was cut down trying to reach his horse to escape.