Who is known as "James of the Glens" in Kidnapped?

James of the Glen is a name given to James Stewart, a Scottish historical figure who was wrongly hanged for the murder of British royal agent Colin Roy Campbell of Glenure, notoriously known as "The Red Fox," in 1752. Stewart had fought with the rebel Highland Jacobites against British troops at Battle of Culloden in 1746. By 1752, he was the leader of the resistance to the British seizure of Scottish tenant farms under the direction of Campbell. Thus, when Campbell was murdered, Stewart became a useful scapegoat for British authorities.
Stewart's unjust murder served as the inspiration for the Robert Louis Stevenson novel Kidnapped. The character of Alan Breck Stewart, who becomes a friend of young David Balfour in the novel, is based on a real person, the foster son of James Stewart. After David witnesses the murder of "The Red Fox" in chapter 17, both he and Alan Breck, who happens to be in the area, are accused of the murder and must flee. When they have a chance to rest, David wishes to part with Alan, believing him responsible for the murder, but the older man is able to put his friend's suspicions at rest. For his part, David understands Alan's antipathy to the Red Fox and the British and knows why he is willing to risk his life to lead the British astray.