The All Factions Unlocked mod is one of the most popular mods here. Most Hosted Mods, if not all, unlock at least some minor factions. Empire Total Factions unlocks minor and emergent factions. Why is playing minor factions popular? Perhaps it's the challenge of playing a smaller nation, fighting not just to expand but to survive. Perhaps it's the attraction of being an 'underdog'. Perhaps people like the idea of leading soldiers who "fight for freedom, a driving force stronger than the word of any general" (this quote is from the the introduction to episode 3 of the Road to Independence campaign).
As I see it, playing a smaller nation requires a different approach on the campaign map and battlefield. This is especially true if you are relying mainly on less powerful units (such as militia, irregular, light and shock troops, as I do when using my Minor & Emergent Factions Unit Pack).
Why are different strategies and tactics needed? Here are some examples:-
1. The challenge of expanding without losing your home region
Playing as a major faction, I often start by taking a region in the Caribbean or the Americas. Playing as Scotland and Savoy, I built one decent-sized army (I could afford only one). As Scotland, I took the pirate-controlled islands in the Caribbean. As Savoy, I took Georgia and Texas. In both campaigns, while my army was in the Americas, a nearby faction in Europe took my home region (Britain took Scotland, Genoa took Savoy's home region). It seems that, if we play as a smaller nation, we need to defeat a neighbouring country first before trying to build a colonial empire.
2. The challenge of avoiding defeat when a nearby nation attacks (and they have a stronger army)
Ambush
Playing as Ireland, I had a similar problem to the previous examples - Britain would attack Ireland after a few turns, in most campaigns. As Ireland, I could not build an army quickly enough which was capable of defeating the army which Britain would send, in a standard battle. So, playing with a mod (which gives more units the 'paths seldom trod' ability), I set up an ambush. To set up an ambush in Empire Total War, you need to:-
- Assembly an army which is only composed of units with the 'paths seldom trod' ability
- Move this army to an area with trees, such as the north of Ireland near the land bridge with Scotland.
- Keep this army still (and unseen by the enemy) for several turns. After that, the figure representing the army on the campaign map crouches down, showing that the army is hidden and ready to ambush.
- If an enemy army attacks, you have the opportunity to intercept them. Take that opportunity and you will ambush them. You will be able to set up your units in locations surrounding the enemy (although this is not always the best way to win) and the enemy army will deploy in a column.
Ambushing is difficult to achieve because you have to be able to predict the path the enemy will take to attack you (and that path has to cross a forest; also, you have to keep your army in that forest unseen for a few turns). I have only been able to ambush another army successfully when playing as Ireland, or when I have found a similar 'choke point' on the campaign map which the enemy army is likely to approach one of my region capitals through.
When an army is crouching on the campaign map, you can send other units with 'paths seldom trod' to join this army (the hidden army remains hidden). This means that you can send your first unit to hide on the campaign map (so that you establish a hidden army before the enemy sends units which can see them) and build up your army by sending more units to join the hidden army.
I have experimented with different tactics in ambushes. The successful tactics were:-
(a) Charge the enemy as soon as the battle begins, while they are still in a column. You can see this tactic in action in this post and the following post.
(b) Form a thin line (two soldiers deep rather than the usual three) of infantry on the far side of a forest from the area where the enemy deploys (if a forest is available; the forest provides some protection from enemy artillery and disrupts the enemy line when they approach.) Hide some early light infantry (if you are using a mod which allows your faction to recruit such a unit, or if you can recruit units such as Rangers, Guerillas or Native American Musket Auxiliaries) in a wooded area, not too close to the enemy. Wait for the enemy army to attack your thin line. When they are engaged, send your hidden light infantry to attack them. If possible, surround them (that is one reason why your infantry line is thin - the other reason is so that they will take fewer casualties). You can see a map illustrating this tactic in this post.
Migrate
Perhaps losing your home region cannot be avoided, or maybe you would like to try a different strategy. It can be possible to play on after losing you home region (this might not work in some situations, for example if you lose your home region in Europe and your only other regions are outside Europe).
For example, playing as Morocco, I successfully defended my capital against a British army. (Some people have criticised the AI for not using naval invasions. Playing as both Hannover and Morocco, I have experienced naval invasions, even when playing on Normal campaign difficulty.) Then a Spanish army attacked and took my home region. Fortunately, Morocco had expanded to the east, taking the regions which belong to the Barbary States at the start, so I could play on.
3. The challenge of paying for the upkeep of your army after the enemy blockades your trade port
When playing as a smaller nation, a nearby country can send ships to blockade the trade port (if you have one) in the region which belongs to your capital city. That can ruin your economy, making it impossible to pay for the upkeep of your army. As a smaller nation, you probably do not have a shipyard which would enable you to build frigates. There are mods such as Empire Total Factions and my Navy Recruitment mod, which allow trade ports to build frigates. However, a minor faction might struggle to pay for the upkeep of both an army and a navy, in the early part of the campaign (and, after your port is blockaded, you cannot build ships there until the blockade is ended).
Here's one possible solution: have a revolution as soon as possible. Why do that? Because, to have a revolution, you set taxes to the maximum level for several turns and do not recruit units or construct buildings. Playing as Ireland, and having a revolution as quickly as possible, I can accumulate a lot of money.
How do you have a revolution? Set taxes to maximum in your capital region (and exempt any other regions you own from taxes, unless you want them to rebel as well). Do not recruit units or build/improve buildings. Move any land units out of your capital (or disband them). Public order, at least for the lower classes, needs to remain below zero for three turns. Wait three turns - you will have a strike, then a riot, then a rebellion. When the rebellion begins, you can side with the government or the rebels - choose the rebels. You will now have control of a rebel army (and nothing else - your regions are greyed out). Capture your capital city. (Then set your taxes back to normal, or you will have another rebellion!). A few factions, such as the Westphalia and the Thirteen Colonies, cannot do this because the rebels belong to a different faction. (If you do this when playing the Thirteen Colonies, the rebels belong to the United States. If you want to play as the Thirteen Colonies, have a rebellion and become a republic, you can do that with my These United Colonies mod, here. On that thread, there is an explanation of how to have a rebellion as the Thirteen Colonies, here).
The money generated by the revolution enables Ireland to sustain an army (and replenish units after battles) even after a British ship has blockaded my only trade port. (Of course, that money will run out eventually - I still need to defeat Britain fairly quickly - but, with the money generated by the revolution, victory becomes possible.)
Perhaps other players who like playing as smaller nations would like to comment on which strategy and tactics work for you? (Of course, this might vary, depending on which mod(s) you are using.)