In July 1385 Richard II, king of England, led an English army into Scotland. The invasion was, in part, retaliation for Scottish border raids, but was most provoked by the arrival of a French army into Scotland the previous summer. England and France were engaged in the Hundred Years' War, and France and Scotland had a treaty to support each other. The English King had only recently come of age, and it was expected that he would play a martial role just as his father, Edward the Black Prince, and grandfather Edward III had done. There was some disagreement amongst the English leadership whether to invade France or Scotland; the King's uncle, John of Gaunt, favoured invading France, to gain him a tactical advantage in Castile, the throne of which he claimed through his wife, Constance, with little success. The King's friends among the nobility – who were also Gaunt's enemies – preferred an invasion of Scotland. A parliament the year before had granted funds for a continental campaign and it was deemed unwise to flout the House of Commons. The Crown could barely afford a big campaign. Richard summoned the feudal levy, which had not been called for many years; this was the last occasion on which it was to be summoned.
Richard promulgated ordinances to maintain discipline in his invasion force, but the campaign was beset by problems from the start. One of Richard's knights was killed by the king's half-brother before the army even reached Newcastle; once there, the leadership was divided and often indulged more in internecine fighting than in fighting against the Scots, who, with their French allies, had retired in the face of the English and refused battle. The Scots scorched the earth as they retired. The invaders swiftly exhausted their food and other supplies; by the time the English reached Edinburgh, they had achieved little of military value, mostly the burning of churches. Gaunt may have proposed chasing the Scots into the mountains to force them to battle, but the King refused to countenance such a tactic and the army soon withdrew to England. As Richard's force left Scotland, the Franco-Scottish army counter-invaded England from the West March getting almost as far as Carlisle and ravaged Cumbria and Durham on its return. Richard was to propose another invasion of Scotland a few years later, but this came to nothing; and on his next invasion, of Ireland in 1399, he was deposed by Gaunt's son, Henry Bolingbroke.