Man for Man, American Indians are more powerful than European soldiers in the first half of the game. Obviously, this is debatable. I personally disagree that Indians, particularly those not armed with firearms, were that effective against European troops. If you look at most Indian victories, they occured when (a) the Indians had adapted to some degree, European technology and/or (b) they had signifcant numerical advantages. There are few, if any examples, of Indians going toe to toe with similar or superior numbers of European or American model infantry and Cavalry.

However, the bigger issue, of course, is that the Indian factions (which historically struggled to put 1,000-2,000 men in the same place by the time of the French and Indian War), are able to put together multiple armies of 1500+ 5-10 years into the game, while European nations are generally fielding armies half their size. Forget that, accepting that the game plays out at somewhere around a 1:5-1:10 scale, the Indian armies in game are often several times bigger, at 1:1, than their real life counterparts.