battalions

A battalion is a military unit typically formed of several companies and commanded by a lieutenant colonel. It is a principal tactical formation capable of independent operations on the battlefield, though it usually operates as part of a brigade or regimental structure. The size and organization of a battalion vary by country and role.

In most modern forces, a battalion numbers roughly 300 to 1,000 soldiers. Its core usually includes a headquarters and headquarters company, three to five maneuver companies (such as infantry, mechanized infantry, armor, or cavalry), and a support company or attached battalion-level elements that provide logistics, medical support, engineers, and communications. A battalion is generally the smallest unit capable of sustained independent operations in the field and is typically commanded by a lieutenant colonel; larger battalions may be led by a colonel.

Types of battalions include infantry, mechanized or armored, airborne or air assault, and specialized formations such as engineer or signals battalions. National doctrines influence exact structure, naming, and integration with other units, but the battalion often forms the building block for brigade-level operations and can employ a variety of combined-arms capabilities within its organization.

Historically, the battalion emerged in early modern Europe as a subdivision of the regiment and evolved into a standard combat unit within larger formations such as brigades. In many armies, regiments have become largely administrative, while battalions serve as the primary deployable combat units in the field. See also brigade and regiment.