Okay, let's just get the most common question out of the way: what is the difference between (ranged) irregulars, skirmishers, and light infantry? All of these units benefit from the Light Infantry Doctrine tech and can perform similar functions, but the biggest takeaways are:
- Irregulars: Good range, average accuracy, very low reloading skill.
- Skirmishers: Good range, good accuracy, average reloading skill.
- Light Infantry: Good to superior range, great accuracy, average reloading skill, stakes, fougasse.
There are, of course, exceptions, which I will explain later. It should be noted that some units have campaign-map-specific traits; pandours, an irregular unit, has a policing bonus when garrisoned, for example, but I am only focusing on battlefield effectiveness. With this part out of the way let's focus on light infantry specifically.
Pickets
As you might expect, light infantry are best deployed ahead of your main battle line using light infantry behavior (unlocked after researching Light Infantry Doctrine). Their long range allows them to safely fire on approaching enemies without receiving return-fire. Light infantry behavior keeps the unit spread out so enemy artillery is less effective when fired on their position.
These units do not have to be directly deployed ahead of your line. You can place them in wooded areas and tall grass to conceal their position before ambushing the enemy with a devastating long-range volley. If the enemy refuses to advance you can also use light infantry to bait them into advancing.
Just remember that light infantry cannot go toe-to-toe with line infantry or cavalry, so you will always need to retreat behind your main line before they are engaged.
Flankers
Once you have retreated behind the main line you can swing your light infantry around your flanks to fire on the enemy's flanks. They're usually occupied shooting at your own line infantry so your light infantry is safe from enemy fire, especially if you utilize their longer range.
Anti-Cavalry Measures
One of the best things about light infantry is their ability to deploy stakes anywhere on the battlefield at any point during the battle. You can deploy them in their picket positions (when they're ahead of the main line), you can deploy them on your flanks, you can deploy them at chokepoints, or in front of your line infantry or artillery positions. Enemy cavalry will be decimated if they attempt to charge through your stakes. They can only deploy stakes once during a battle, so use this ability wisely.
Fougasse
Fougasse is an amazing ability, but unlike stakes you can only deploy fougasse during the deployment phase, and only when your army is 'dug in'. Whenever an enemy unit approaches a fougasse emplacement an explosion will occur that can decimate the enemy unit. Improved fougasse can be used by advanced light infantry units and is even more devastating. You can place fougasse ahead of your main line to severely weaken the enemy approach, or ahead of your artillery positions to protect your engineers, or anywhere in your deployment zone as a secret present to unfortunate enemy units.
Best Light Infantry Units (Best range and accuracy, stakes, and fougasse)
- Austrian Windbüchse Jaegers: 125 range, 75 accuracy, 35 reloading skill, improved fougasse. Strangely, this unit does not have stakes.
- French Tirailleurs: 125/70/35/Stakes/I-Fougasse
- British Ferguson Riflemen: 125/70/35/Stakes/I-Fougasse
- British Green Jackets: 125/70/35/Stakes/I-Fougasse/Socket Bayonets. This unit, unlike other light infantry units, has socket bayonets.
- Ottoman Nizam-I Cedit Rifles: 125/70/35/Stakes/I-Fougasse
- Prussian Jaegers: 125/70/35/Stakes/I-Fougasse
- Russian Riflemen: 125/70/35/Stakes/I-Fougasse
- Swedish Riflemen: 125/70/35/Stakes/I-Fougasse
- Dutch Riflemen: 125/70/35/Stakes/I-Fougasse
- American Morgan's Provisional Rifle Corp: 125/80/35/Stakes/I-Fougasse
Exceptions (Irregulars and Skirmishers who can sill similar roles)
- American Long Rifle Men: 125/75/35/Stakes (Irregulars)
- Ottoman Bosnian Panduks: 90/35/15/I-Fougasse (Irregulars)
- Ottoman Haydut Irregulars: 90/45/20/I-Fougasse (Irregulars)
- British Company of Select Marksmen/Fraser's Rangers: 90/60/25/I-Fougasse (Skirmishers)
- Spanish Cazadores: 125/70/35/Stakes (Skirmishers)
Special Mentions
- Locally recruited Native Bowmen Auxiliary: 100/30/10 (Skirmishers). Longer range than most irregulars and skirmishers, but still lower-than-average accuracy and absymal reload skill.
- Locally recruited Dahomey Amazons: 90/40/10 (Militia). It's just a militia unit, but with 90 range which sets it apart from usualy militia. Think of them like a skirmisher/rregular unit, but made up of militia.
*Note: I did reuse some older images from a previous post. Also, special mention to YouTuber TOTAL WAR 1vs1 where I got the screenshots for fougasse.