Skirmishers

Skirmishers are light infantry or cavalry soldiers stationed to act as a vanguard, flank guard, or rearguard, screening a tactical position or a larger body of friendly troops from enemy advances. They are usually deployed in a skirmish line — an irregular open formation much more spread out in depth and breadth than a traditional line formation. Their purpose is to harass the enemy — engaging them in only light or sporadic combat in order to delay their movement, disrupt their attack, or weaken their morale. Skirmishers' open formations and smaller numbers can give them superior mobility over the regular forces, allowing them to fight on more favorable terms, taking advantage of better position or terrain and quickly withdrawing from any threat of superior enemy forces.

Skirmishers can be either regular army units temporarily detached to perform skirmishing, or specialty units specifically armed and trained for such low-level irregular warfare tactics. Light infantry, light cavalry, and irregular units often specialize in skirmishing.

Though often critical in screening the main army from sudden enemy attacks, skirmishers are poor at taking and defending ground from heavy infantry or heavy cavalry. In modern times, following the obsolescence of such heavy troops, all infantry has become indistinguishable from skirmishers, and the term has lost military meaning.

Those acting as skirmishers are said to skirmish. A battle with only light, relatively indecisive combat is often called a skirmish.

In ancient and medieval warfare, skirmishers typically carried bows, javelins, slings, and sometimes light shields. Acting as light infantry with their light arms and minimal armour, they could run ahead of the main battle line, release a volley of arrows, slingshots or javelins, and retreat behind their main battle line before the clash of the opposing main forces. The aims of skirmishing were to disrupt enemy formations by causing casualties before the main battle, and to tempt the opposing infantry into attacking prematurely, throwing their organization into disarray. Skirmishers could also be effectively used to surround opposing soldiers in the absence of friendly cavalry.

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