There is conflicting information on this subject and the truth may never be known for sure.
As far as I know the strongest tradition in favor of the Guards having carried colours in America are the Third Guards colours in the Guards Chapel in London. They were donated by the family of Lt. Col. Sir George Osborn, who commanded a company of Guards in America for several years. Those who have examined them, however, feel that they are not worn out enough to have been carried on campaign.
What may be the only contemporary statement about Guards colours in America is in the journal of Ensign Glyn (Princeton Univ. Manuscript Dept.). On Oct. 19th, 1776 he wrote "The King has been pleased to appoint Ensign Glyn to be a Lieutenant in the first Regiment of Foot Guards, his Commission bearing date 15th June last. It is likewise his Majestys pleasure that he remains with the Detachment their being no Colours." While that statement is vague, Glyn stayed with the same company in America as the third officer. Evidently this was the result of the fact that there were no company colours and, therefore, no need for an ensign to carry them.
I'd enjoy finding out whether you have further evidence that the Guards did have colours in America.
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