Americas Campaign

[PBI]

All your mounted conquistadors will be insanely powerful and are basically your main killing tool. Since the native factions only field infantry, your conquistadors can simply charge anything that isn't a spear unit and suffer scarcely any losses while inflicting huge damage.

Your culverins are also pretty handy, their accuracy has been greatly increased from vanilla so they are pretty effective for sniping the enemy general (or just tearing holes through any enemy unit you don't like the look of).

The basic strategy I found most effective, was a battle line of native mercenaries to pin the enemy and absorb losses, strengthened at key points with dismounted conquistadors/ sword and buckler men, then a crushing conquistador charge to the flanks and rear (almost always possible due to the lack of enemy cavalry). Doubly effective if you've managed to soften up the enemy and pick off the general with culverin fire beforehand.

The only units I wouldn't bother with too much, are pike militia, and musketeers/crossbows. The first are essentially useless since the enemy have no cavalry, while the latter, while in principle pretty powerful, will struggle to make any significant impact due to the sheer numbers of enemy troops you will face.

I found the main problem early on is not the native armies you face as such, so much as the shortage of troops and the large garrisons needed to maintain order. Generally I found it helps to get into the spirit of the conquistadors, and take the attitude that while heavy losses in your Spanish troops (especially your cavalry) are unacceptable, the lives of your native mercenaries are entirely expendable. So long as you can keep the momentum of conquest going, you will be periodically rewarded with new conquistador stacks arriving, as well as being able to upgrade your cities to get your best troops.

[Lancome]

How about late game? Am I going to get stuck with Mercenary natives, Native warriors,and archers?

[Monsieur Alphonse]

During late game you will have lots of conquistadores (mounted and dismounted) and your uber unit: Spanish dragoons.

[PBI]

As you conquer more territory you will gradually get promoted by the King of Spain, which will allow you to build more advanced troop types from your cities, letting you replace your troops and lessening the need be so careful to avoid losses among your Spanish troops. I imagine you can eventually phase out native mercenaries altogether except for pure cannon-fodder duty like manning rams or soaking up arrow fire, though to be honest I gave up on the campaign around the point I got access to the highest level of troop buildings, since I was finding it a bit easy and repetitive by that stage. I doubt you will ever be able to spam Spanish troops to the point where you match or outnumber the native armies, but you shouldn't ever need to.

Just be sure to focus on melee tactics (with a little supporting gunfire), to get the most out of your men's advantages in weapons, armour and hitpoints, and avoid excessive skirmishing or missile duels, where disparity in numbers counts for more.

[anweRU]

To the above, I would add that encircling the enemy line will the cavalry causes the enemy to stop for a few seconds, and reform - without the cavalry attacking. The culverin(s) will do better against these stationary targets. I haven't managed to halt them for more that two or three times, but it is a nice little bonus.

Once the natives get too close, then it is time for a rear-charge. Generals and those pesky priest units are my first priorities...

[oz_wwjd]

Once I got teched up, I took the approach off launching a mass calvary attack on the weakest point of my enemy's lines and smashing them. Most of the native units tended to rout on impact when I did that,and I never gave them the chance to build priests,or I only ever saw 2-3 units of them anyways.
Losses were acceptable seeing I have 4 cities that were producing 8 conquistadors per turn..

[Careless]

It is also possible to recruit better mercenaries. If you make alliances with the various factions and send generals near their territory (into their natural territory?) you can find two different unit types to recruit. Eagle and Arrow soldiers from Aztec, Dog Boys and Apache Braves from Apache, etc. Basically, mid-level units from the factions that are clearly better than the ones you'd normally recruit, but not particularly powerful. They can also be retrained in some cities, although I haven't figured out how to predict which ones can be retrained in which cities.

As for the pikemen, the the Chich... the black banner natives in the West of the map can get melee cavalry (although I've yet to see it happen) and the French and the English might attack you for no apparent reason.

[anweRU]

I used pike militia exclusively as garrison troops. You'll need lots of soldiers (not units) to maintain order. 1 pike militia = 2x sword militia. I used the free upkeep to the max, and some native mercenaries for the rest of the required garrison.

I won the campaign before the English even appeared, and the French never attacked a single settlement or AI faction. The French stacks just stood there in Florida, admiring their pretty costumes I suppose...