unabated, into 1321, resulting in a string of bad harvests. Revenues from the exports of wool plummeted and the price of food rose, despite attempts by Edward's government to control prices. Edward called for hoarders to release food, and tried to encourage both internal trade and the importation of grain, but with little success. The requisitioning of provisions for the royal court during the famine years only added to tensions. Meanwhile, Robert the Bruce exploited his victory at Bannockburn to raid northern England, initially attacking Carlisle and Berwick, and then reaching further south into Lancashire and Yorkshire, even threatening York itself. Edward undertook an expensive but unsuccessful campaign to stem the advance in 1319, but the famine made it increasingly difficult to keep his garrisons supplied with food. Meanwhile, a Scottish expedition led by Robert's brother Edward Bruce successfully invaded Ireland in 1315. Edward Bruce declared himself the High King of Ireland. He was finally defeated in 1318 by Edward II's Irish justiciar, Edmund Butler, at the Battle of Faughart, and Edward Bruce's severed head was sent back to Edward II. Revolts also broke out in Lancashire and Bristol in 1315, and in Glamorgan in Wales in 1316, but were suppressed. The famine and the Scottish policy were felt to be a punishment from God, and complaints about Edward multiplied, one contemporary poem describing the "Evil Times of Edward II". Many criticised Edward's "improper" and ignoble interest in rural pursuits. In 1318, a mentally ill man named John of Powderham appeared in Oxford, claiming that he was the real Edward II, and that Edward was a changeling, swapped at birth. John was duly executed, but his claims resonated with those criticising Edward for his lack of regal behaviour and steady leadership. Opposition also grew around Edward's treatment of his royal favourites. Edward had managed to retain some of his previous advisers, despite attempts by the Ordainers to remove them, and divided the extensive de Clare inheritance among two of his new favourites, the former household knights Hugh Audley and Roger Damory, instantly making them extremely rich. Many of the moderates who had helped deliver the peaceful compromise in 1318 now began to turn against Edward, making violence ever more likely. Later reign (1321–1326) The Despenser War The long-threatened civil war finally broke out in England in 1321, triggered by the tension between many of the barons and the royal favourites,