In April 1318, Berwick-upon-Tweed, the last Scottish stronghold which was in the hands of the English, was captured by Sir James Douglas and Thomas Randolph, Earl of Moray, two of King Robert Bruce's most able commanders.

Ever since his defeat at Bannockburn in 1314, Edward II had been preoccupied by an ongoing political struggle with his senior barons, headed by Thomas, Earl of Lancaster.

Vigorous assaults were made on Berwick by land and sea, but Walter, the High Stewart of Scotland, ably assisted by John Crabb, a military engineer, conducted an effective defence, beating back all attacks.

King Robert had no intention of risking a direct attack on the powerful English army which, in the words of John Barbour, 'might well turn to folly'.

[5] From the gates of York, Melton's host marched out to face the battle-hardened schiltrons, some 3 miles (5 km) east of Boroughbridge, where the rivers Swale and Ure meet at Myton.

And when the Englishmen at last heard of this thing, all that might travel-as well as monks and priests and friars and canons and seculars-come and meet with the Scots at Myton-on-Swale, the 12th day of October.

At Berwick it caused a serious split in the army between those like the king and the southerners, who wished to continue the siege, and those like Lancaster and the northerners, who were anxious about their homes and property.

To make matters worse, no sooner had the royal army disbanded than Douglas came back over the border and carried out a destructive raid into Cumberland and Westmorland.