Basically, It is the green, blue and black of the ancient "Black Watch" Plaid. The following taken off the web.....The Black Watch also has a very complicated story. We know the tartan was implemented for use by the Highland Companies in 1725. Where it was derived from is up for debate. Some say it was an original design, new at the time. Some say it was an older Campbell tartan. Others argue that it was woven as the basis of several diverse tartans already in use at the time.

So, as for the origin of this tartan, we simply don't have enough proof to say. However, we do know it was adopted for use in 1725, and so was a pre-Culloden tartan. 

Scottish Tartans Museum
86 East Main St. * Franklin NC 29734 * (828)524-7472 * tartans@scottishtartans.org
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What are the Authentic Campbell Tartans?

Many a Campbell and member of a Campbell sept has sought the answer to that question upon first becoming interested in his or her Scottish heritage. Unfortunately, many have looked to the wrong sources for the answer--namely, to merchants selling tartan goods. There is only one authority on the correct tartan or tartans of a clan: the chief of that clan. Not even the Scottish Tartans Society or the Lord Lyon King of Arms claim such authority--they are purely archivists of tartan history, which is, at best, a confused and confusing field.

Here is how our late chief, The 12th Duke of Argyll, and re-affirmed by our current Chief, The 13th Duke of Argyll, MacCailein Mor, summed up the official position on Campbell tartans consistently declared for well over one hundred years by successive Chiefs of Clan Campbell:

      "...the only tartans which I recognize are, firstly, the one you see me and my wife wearing, which goes under various names, such as ordinary Campbell, Ancient Campbell, etc., and all members of our clan who are not specifically identified with [the Houses of Breadalbane, Cawdor [or] Loudoun are entitled to wear it.

      Let me get rid, once and for all, of the thought that there is a 'Campbell of Argyll' [tartan]. While it is true that the Sixth Duke [of Argyll] introduced a white line to his plain Campbell tartan to differentiate himself from the rest of the Campbells, (he being the chief and entitled to do so), he was the only member of the family so to do and the rest of the family thought he was rather pompous to do it.

      Campbell of Breadalbane--fine [to wear].

      Campbell of Cawdor--fine.

      Campbell of Loudoun--fine.

      Campbell of Glenlyon--I have never heard of it.

      Campbell of Loch Awe-this is plain ridiculous, as we are all Campbells of Loch Awe originally. - Apart from anything else, I have never heard of a Campbell of Loch Awe tartan, nor do I wish to do so.

      THERE IS NO DRESS CAMPBELL [TARTAN]--repeat! repeat! repeat!

      There is NO HUNTING CAMPBELL.

      There is NO CAMPRELL RED.

      There is NO CAMPBELL - SIMPSON.

      There are no Campbell cheques, other than commercial ones...

      If I feel strongly about anything and would like it inscribed on my tombstone, there might be a few lines such as 'All Campbells with the exception of the three principal septs [the Houses of Breadalbane, Cawdor and Loudoun] should wear plain undifferentiated Campbell for evermore and not get confused by peddlers of this [other] material that comes under all sorts of guises.

Yours ever,

Your Kinsman and Chief,
Argyll
            [From a letter to William A. Mitchell. late Clan Campbell Society U.S.A. genealogist]
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To summarize, there are just four authentic Campbell tartans: Ancient or "plain" Campbell, Campbell of Breadalbane, Campbell of Cawdor, and Campbell of Loudoun. To be faithful to Scottish tradition, only those descended from the Houses of Breadalbane, Cawdor and Loudoun should wear the tartans belonging to those houses; all other Campbells and members of other Campbell septs should wear Ancient or "plain" Campbell tartan, which is composed of threads of only three colors: blue, green and black--with no overstripes of any other color.

    Ancient Campbell is the same as Black Watch tartan--hardly surprising, since that illustrious regiment is a Campbell regiment, raised by the Duke of Argyll in 1739. (Indeed, as Alastair Campbell of Airds Yr., Chief Executive of Clan Campbell, has indicated in his authoritative book Campbell Tartan, the Black Watch tartan may well have been adopted as the clan's tartan because so many members of the clan were already wearing it, owing to their service in the regiment.)

     The Black Watch tartan is today usually made in darker shades of green and blue, while Ancient Campbell is made in lighter, brighter shades. Some Campbells wear the lighter Ancient Campbell for day wear and the darker Black Watch for evening and formal wear--the important point being that they are the same tartan. Remember, it is the "sett", or thread count of a tartan that distinguishes it from other tartans, not the comparative lightness or darkness of their colors, which in early days could vary greatly due to the unpredictable nature of vegetable dyes. So, caveat emptor: before you buy anything purporting to be Ancient Campbell or Black Watch tartan, be sure it has the correct sett, with first one pair of black "tramlines" on the blue, and then two pair, then one pair, and so on.