Warwick and John's army defeated. The Earl escaped; Montagu was captured and sent to York Castle. It seems probable that he escaped execution after the battle because, as the Milanese Ambassador wrote, "a brother of my lord of Somerset is a prisoner [of Warwick's] at Calais." As a result of his capture and imprisonment in York, Montagu escaped participation in the biggest and probably bloodiest battle of the Wars of the Roses which took place on 29 March 1461 at Towton in Yorkshire. This decisive Yorkist victory led to Montagu being released the next day, when the son of the Duke of York – and England's de facto new king – Edward IV entered York in triumph. Montagu and Warwick then stayed in the north to attempt the recapture of northern castles still in Lancastrian hands; as John Gillingham has put it, "the unfinished military business would have to be left to the Nevilles." And on 10 May 1461 Montagu was commissioned to raise troops against both the Lancastrian remnants and the king of Scotland. One of Montagu's first actions was to successfully raise the siege of Carlisle, "with prompt action." Carlisle had had its suburbs burnt and been under siege from June by a Scottish-Lancastrian force, but was easily relieved by him, apparently killing 6,000 Scots and Lord Clifford's brother in the process, before Warwick had even arrived. The military campaign that followed was focused on the recapture of strategically vital castles on the Northumbrian border. Alnwick Castle was commanded by a shell keep, to which extra towers had been added, as well as to the curtain wall, with a solid barbican and gatehouse. Bamburgh Castle was on a high spur ridge with three baileys, a large keep, and fortified gateways. Dunstanburgh Castle stood on a dolerite spur which had the sheer drop of a cliff on one side. Montagu besieged Bamburgh, the most important of these northern bulwarks, due to its distance from London and proximity to Scotland. By 26 December 1462, when the garrison surrendered, they "had been reduced to eating their horses." Montagu joined Warwick in escorting the chariot of six horses in the funeral cortege conveying the mortal remains of their father and brother from Pontefract Castle to the family mausoleum at Bisham Abbey, on 14–15 February 1463. On 6 May he was appointed Warden of the Eastern March; Warwick was his counterpart on the