Although they may look like normal Musketeers, don't be fooled by their appearance, especially in the Mercantile Era when they seem to have a very slovenly appearance: Leathernecks are some of the post powerful units in the American arsenal, given their propensity for fortifying themselves after being idle without the need of a General to issue the order. When used properly in tandem with other units of the American arsenal, Leathernecks can be a very powerful component of your military, especially in stopping attacks by cavalry owing to their ability to entrench themselves. This is especially moreso since these units are costly, and the Americans don't have much of an economic bonus unlike the British or the Dutch who are avid users of Marine-type units.
For maximum effect, look for patches of rocky terrain to entrench them, since they still count as light infantry and get an additional 33% defence bonus when standing on rocky terrain. You can use these units as "moving anchors", especially in defending your Rangers from being cut down by cavalry, given that Leathernecks also have an attack bonus versus mounted units.
Should you see your enemy raising Leathernecks, you should never think of charging them head-on with cavalry. Instead, bring up more Light Infantry or Musketeers to mob them with sheer numbers, or use big guns instead — Flying Artillerty are highly effective counters for Leathernecks and most infantry. Equally, you can also choose to bypass them instead, thus saving yourself the trouble of having to fight them toe on to and suffer immeasurable losses.
- Digging In — Because they can automatically entrench themselves with no need of Generals, Leathernecks are ideal for stiffening the front line, or or holding defensive positions.
- Buyer Beware — The cost of raising Leathernecks means that you can't rely on them solely for defence, they are best used as escorts for weaker units or to spearhead assaults.
It isn't known exactly how the term 'leatherneck" came about, but from the late 18th century onward it has been used as a reference to the Marine Corps of the United States of America, as well as its antecedents, mainly the Continental Marines and the United States Marines. Several variations exist, but the most common ones are that either it refers to the practice of issuing leather collars to function as armour, or that it refers to the tanned and rough appearance of the necks of marines (owing to their extensive exposure to the sun while aboard ships).
Whatever the true reason, the "Leathernecks" first appeared back in the 18th century during the American War of Independence against Britain. To support the 13 colonies in the struggle for independence, a committee of the Continental Congress raised a resolution calling for two battalions of Marines able to fight for independence at sea and on shore. The resolution was approved on November 10, 1775, officially forming the Continental Marines During the war , the Marines distinguished themselves at the battle of Nassau (1776), which was a raid on a British base in the Bahamas. The Continental Marines also had the distinction in playing a pivotal role in the history of banking: their last task prior to disbanding was to defend a shipment of silver on loan from France meant to help set up the First Bank of the United States.
However it was soon shown that disbanding the Continental Marines (in order to save money in a new impoverished nation) was a mistake, and they were soon revived as the United States Marines and subsequently served in two conflicts: the War of 1812 with Britain where they fought mainly at sea, and at the battle of Derna (1805) as part of the First Barbary War. It is though that the origin of their nickname, "Leathernecks" comes from this conflict, owing to the leather stocks issued to be worn around the neck to help protect soldiers in combat at close quarters.