The king failed to arrive to lead the English army and the result was intermittent skirmishing until early 1482. Richard witnessed the treaty with Alexander, Duke of Albany, brother of King James III of Scotland. Northumberland, Stanley, Dorset, Sir Edward Woodville, and Richard with approximately 20,000 men took the town of Berwick as part of the English invasion of Scotland. The castle held until 24 August 1482, when Richard recaptured Berwick-upon-Tweed from the Kingdom of Scotland. Although it is debatable whether the English victory was due more to internal Scottish divisions rather than any outstanding military prowess by Richard, it was the last time that the Royal Burgh of Berwick changed hands between the two realms. Lord Protector On the death of Edward IV on 9 April 1483, his 12-year-old son, Edward V, succeeded him. Richard was named Lord Protector of the Realm and at Baron Hastings' urging, Richard assumed his role and left his base in Yorkshire for London. On 29 April, as previously agreed, Richard and his cousin, Henry Stafford, 2nd Duke of Buckingham, met Queen Elizabeth's brother, Anthony Woodville, Earl Rivers, at Northampton. At the queen's request, Earl Rivers was escorting the young king to London with an armed escort of 2,000 men, while Richard and Buckingham's joint escort was 600 men. Edward V had been sent further south to Stony Stratford. At first convivial, Richard had Earl Rivers, his nephew Richard Grey and his associate, Thomas Vaughan, arrested. They were taken to Pontefract Castle, where they were executed on 25 June on the charge of treason against the Lord Protector after appearing before a tribunal led by Henry Percy, 4th Earl of Northumberland. Rivers had appointed Richard as executor of his will. After having Rivers arrested, Richard and Buckingham moved to Stony Stratford, where Richard informed Edward V of a plot aimed at denying him his role as protector and whose perpetrators had been dealt with. He proceeded to escort the king to London. They entered the city on 4 May, displaying the carriages of weapons Rivers had taken with his 2,000-man army. Richard first accommodated Edward in the Bishop's apartments; then, on Buckingham's suggestion, the king was moved to the royal apartments of the Tower of London, where kings customarily awaited their coronation. Within the year 1483, Richard had moved himself to the grandeur of Crosby Hall, London, then in Bishopsgate in the City of