A skilled young knight, Hereford was Edward’s brother-in-law – but had not always supported him. As Constable of England he had rights of command in the army and had experienced the realities of fighting as well as the chivalry of the jousting field.
He had been given Bruce’s own castle of Lochmaben by Edward I and so must have felt a personal edge to the conflict.
Hereford quarrelled with Gloucester as to who had the right to lead the vanguard. The king decided that the duty should be shared, but this just caused confusion and anger in the English army.
On 23 June as the cavalry approached the Scots, Hereford was appalled by the slaughter of his nephew, Henry de Bohun, by Bruce himself. Next day Hereford’s cavalry had another disastrous encounter with the Scots, with no room to manoeuvre and powerless against the spearmen.
Hereford fled to English-controlled Bothwell Castle – but found himself trapped when the keeper of the castle switched sides and handed him over to Bruce. He was a valuable hostage, and was exchanged for a ransom of important prisoners, including Bruce’s wife Elizabeth.