those daring to assert Scotland's independence. On 22 July, Edward's army attacked a much smaller Scottish force led by Wallace near Falkirk. The English army had a technological advantage. Longbowmen slaughtered Wallace's spearmen and cavalry by firing scores of arrows over great distances. Many Scots were killed at the Battle of Falkirk. (It is impossible to give a precise number of the dead.) Despite the victory, Edward and his army soon returned to England and thus failed to subdue Scotland completely. But the defeat had ruined Wallace's military reputation. He retreated to thick woods nearby and resigned his guardianship in December. From Falkirk to execution Wallace was succeeded as Guardian of the Kingdom jointly by Robert Bruce and John Comyn, but they could not see past their personal differences. This brought another shift in the political situation. During 1299, diplomatic pressure from France and Rome persuaded Edward to release the imprisoned King John into the custody of the Pope. The papacy also condemned Edward's invasions and occupation of Scotland in the Papal bull Scimus, Fili. The bull ordered Edward to desist his attacks and start negotiations with Scotland. However, Edward ignored the bull. William Wallace was sent to Europe to try to gain further support for the Scottish cause. Wallace went to France to seek the aid of Philip IV, and he possibly went on to Rome. William Lamberton, Bishop of St Andrews, was appointed as a third, neutral Guardian to try to maintain order between Bruce and Comyn. The Scots also recaptured Stirling Castle. In May 1300, Edward I led a campaign into Scotland, invading Annandale and Galloway. Edward I's invasion force in the 1300 border campaign is one of the best-documented English armies of the medieval period. The king issued summons in December 1299 asking for feudal service from his magnates across the realm (with the exception of Wales, which Edward stated 'have leave to remain home, because of all the great work they have done in our service in the past'). The roll recording for the army showed that 40 knights and 366 mounted serjeants responded to this request with unpaid service, with a serjeant being counted as equal in worth to one half of a knight. Also accompanying them was 850 paid househeld men, mostly from the royal household. Several earls, such as the Earl of Gloucester and the Earl of Lincoln, showed up in person,