Colin Campbell, 1st Earl of Argyll (died 10 May 1493) was a medieval Scottish nobleman, peer, and politician. He was the son of Archibald Campbell, Master of Campbell, and Elizabeth Somerville. He had the sobriquet Colin Mulle, Bold Earl Colin.
In 1453, when his father died, young Colin was placed in the custody of his uncle, Colin Campbell, 1st of Glenorchy, and succeeded his grandfather Duncan Campbell, 1st Lord Campbell, to become 2nd Lord Campbell. In 1457, he was created Earl of Argyll by James II, who was grateful for the loyalty of his father during the troubles early in his reign.
In 1460, he had a commission as Bailie of Cowal.
Glenorchy arranged a marriage for Argyll with Isabella Stewart, daughter and co-heiress of John Stewart, 2nd Lord Lorne. Through this marriage, Argyll received the Castle of Gloom and the neighboring estate in the parish of Dollar in Clackmananshire, the name of which he changed to Castle Campbell in February 1490.
The exact date of the marriage is unknown, but in 1460, shortly after the boy-king James III came to the throne, Argyll was called upon to intervene in a feud in his wife’s family. Allan MacDougall (called Allan of Lorne of the Wood), desiring to hold the estates belonging to his older brother John Ker of Lorne, seized his brother and imprisoned him in a dungeon on the island of Kerrera, with the intention of starving him to death. Argyll appeared with a fleet of war galleys and completely defeated Allan, burning his fleet, killing most of his men, and restoring the elder brother to his rightful inheritance.
Argyll was often sent on diplomatic missions, the first being in 1463, when James III sent him to negotiate a truce with Edward IV of England. One of the main terms of that truce was that neither king would support the enemies of the other.
In 1464 Campbell was made master of the king’s household, and in 1465, he was appointed Lord Justiciary of Scotland south of the Firth of Forth, a position he held in conjunction with Robert, Lord Boyd, until Boyd fell out with the king and fled to England, at which time Campbell held the position alone.