A Quick Summary of MacGregor History From http://hal_macgregor.tripod.com/gregor/Gregor.htm

“S’RIOGHAL MO DHREAM” (Royal is my race) is the claim of this, one of the most famous of Highland clans, and the principal branch of the Siol Alpin.  The clan claims descent from King Grig, the last 100% Pict to rule Albann, in the ninth century.
The ancestral home of the clan was the western highlands of Perthshire, including Glendochart, Glenstrae, Glenlyon and Glengyle.  Their earliest possession in  Argyll, was Glenorchy,  which was bestowed on the MacGregors for services rendered to Alexander II in his conquest of Argyll.  For a long time the MacGregors maintained possession of their lands by right of the sword, as was the ancient Scottish tradition.  The Campbells, by political clout and treachery, obtained grants of Loch Awe and other MacGregor lands.  Royal Commissions of Fire and Sword were issued against the MacGregors in 1488, 1563, 1589, and 1603.  Finally, in 1604, the name MacGregor was banned,  and efforts were made to annihilate the clan.  Nevertheless, Clan Gregor  supported the Stewart cause in the 17th and 18th centuries.   Charles II, because of their support, repealed the acts against Clan Gregor. This was confirmed by Cromwell, but  upon the accession of William of Orange, upon Campbell pressure, the acts of proscription were renewed due to appeals by the 7th Duke of Argyll.  One of the most horrific acts of revenge on behalf of the Campbells during this renewal, was the death by sustained torture of Lt. Colonel Donald Glas MacGregor, father to Rob Roy MacGregor and chief of the Glen Gyle MacGregors. It was not until 1775 that the penal statutes against the MacGregors were finally repealed, and not until 1784 did the British government bureaucracy finally enforce this edict..   In 1822, Sir Walter E. Scott arranged for clan Gregor to form the official bodyguard for King George IV when he visited Scotland, and in that same year, the clan Gregor Society was formed.  A meeting of the clan was held, where John Murray of Lanrick, afterwards Sir John MacGregor, Bart., descended from the house of Glenstrae, was recognized as chief.

There has never been any apology or recognition of universally recognized criminal acts against the MacGregor extended family by the British authorities.