Robert Munro, 6th Baron of Foulis well have had Munros with him when he was captured at the Battle of Dunbar (1296). It was the Earl's son "Sir Walter the Ros" who fought at the Battle of Bannockburn in 1314 where the Scottish army defeated the English and Robert Munro is said to have fought there with him. General Stewart later included the Munros in the list of Highland clans who fought at Bannockburn. Robert Munro is said to have survived the battle but according to tradition his son George was killed and Robert was therefore later succeeded by his grandson, also called George. Robert's second
Robert the Bruce planned a major military campaign with the support of Lancaster and the barons, mustering a large army of between 15,000 and 20,000 men. In the spring of 1314, Edward Bruce laid siege to Stirling Castle, a key fortification in Scotland whose governor, Philip de Mowbray, agreed to capitulate if not relieved before 24 June 1314. In March, James Douglas captured Roxburgh, and Randolph captured Edinburgh Castle, while in May, Bruce again raided England and subdued the Isle of Man. News of the agreement regarding Stirling Castle reached the English king in late May, and he decided to speed his march