All I have on this subject is here: http://online.offshore.com.ai/~mccown/septs/king.html
which reads, in part, "From Stephen L. Calhoun's List of Spellings, Cadets, and Septs: King most likely became a sept name of Colquhoun from some of the proscribed MacGregors who are said to have adopted this name and then became clients of the Chiefs of Colquhoun. The name MacGregor or just Gregor is also used by longtime tenets of the Colquhoun of Luss."
I checked google to see who proscribed the MacGregors and when. http://members.tripod.com/~Hal_MacGregor/gregor/pride.html
says this: "The Stuarts, had proscribed the MacGregors in the late 1500s and again in 1603 under the influence of the Campbells. . ." http://www.scottielad.supanet.com/helensburgh/
has this: "A small place lying on the East shore of the Gareloch with vestiges of ancient castle and chapel, in Rhu parish, Dunbartonshire. This is the site of a large Royal Naval Submarine base. Just past Faslane a road on the right takes you into Glen Fruin - The Glen of Weeping. It was here in 1603 that the MacGregors ambushed the Colquhouns and more than 100 of the Colquhouns were killed in the slaughter. The MacGregors went on to plunder and pillage Colquhoun lands and the King was so incensed that he stripped the MacGregors of their lands outlawed them and ordered that their name be proscribed. The MacGregors, the clan of Rob Roy MacGregor, were landless and nameless. Scott wrote another famous novel all about them called Rob Roy ." The story of the battle, in greater detail, is at http://www.fortunecity.com/millenium/bankhead/435/origins.ht...
. It begins: "On February 7, 1603, one of the most savage interclan battles occurred in Scotland at Glen Furin near Loch Lomond. The Clan MacGregor and Clan Colquhoun fought a desperate battle which resulted in the defeat of the Colquhouns and the outlawing of the unfortunate MacGregors." The story also appears at http://www.clangregor.org/macgregor/article-glenfruin.html
-- The Political Context of the Battle of Glen Fruin.
Piecing the story together, it seems that the Colquhouns, in spite of the battle of 1603, came to be the protectors of some of the proscribed MacGregors who then took the name King.
Some of the suppressed MacGregors took the name Orr.
Some of the many spelling variants of Colquhoun are Cahoon and Cahoone. My ancestor, William Cahoon, is the subject of http://freepages.genealogy.rootsweb.com/~greenefamily/greene...