I bought these figures several years ago as part of a Seven Years War group. I have always assumed them to be Minifigs either AWI Light Infantry or from the French and Indian War. However, having looked several times I have been unable to find these figures in the Minifigs catalogue:
Annoyingly the bases have been cut down and there are no numbers visible. but, on one I can make out CW, which makes me think they were originally ACW (American Civil War). On closer examination I can see trousers and I think the hats (Kepis) have been filed down and a new front plate added to depict a Light Infantry helmet. What they were originally, I am still not sure.