Scottish Protestant who supported Mary, Queen of Scots.

Campbell succeeded his father, Archibald, the 4th earl, in 1558. He was an adherent of John Knox and assisted Lord James Stewart (afterward the regent Moray (Moray, James Stewart, 1st Earl of, Earl Of Mar, Lord Abernethy)) in the warfare of the lords of the congregation against the regent Mary of Lorraine, the mother of Mary Stuart. Argyll's support of Mary Stuart after her return to Scotland (1561) gradually separated him from John Knox's party. When Mary escaped from Lochleven Castle in 1568, he commanded her forces during the few days that preceded her flight to England. He then made his peace with Moray, although he may have connived at Moray's murder in 1570. He became lord high chancellor of Scotland in 1572. His first wife was an illegitimate daughter of James V, and he was thus half brother-in-law to Mary and Moray.