Awesome artwork “Roicroi, the last tercio” by Augusto Ferrer-Dalmau, portraying infantry of a Spanish tercio at the 1643 Battle of Rocroi, in Wikipedia “Infantry” under license https://creativecommons.org/licenses/by-sa/3.0/deed.en
(2) INFANTRY WAR
Where prehistoric war goes to the origin of war itself, infantry war goes to the fundamental nature of historic war, enduring as its foundation and the predominant means of waging it. Historic war commenced as infantry war and has largely endured as it.
That’s not to say that prehistoric war wasn’t also infantry war. In the broadest usage of infantry war as fighting on foot, all prehistoric war was infantry war (except to the extent of anyone ramming canoes or rafts into each other) – but for the most part, prehistoric war lacked the characteristic drill or regimen of infantry war, fighting as warriors rather than soldiers.
And that’s the essential nature of infantry war – fighting on foot and in formation, coordinated with each other rather solo-ing off into single combat, as soldiers with drill and regimen, typically with standardized weapons and equipment.
As such, the origins of infantry war are the origins of war itself in recorded history, since the first ancient empires fought with regular infantry, albeit often as an elite supplemented by conscript masses or militia as irregular infantry – something that has surprisingly endured as a practice since then to the modern period.
The ancient archetype of regular infantry remains the Greek phalanx, and even more so, the Roman legion.
While the archetypal infantry travels on foot – marches, that is, in a style and pace that has remained remarkably consistent throughout history – the defining trait of infantry is that they fight on foot, not necessarily that they get to the fight on foot.
Hence, there has been a variety of infantry distinguished by getting to the fight by other means than marching to it – most notably mechanized infantry or mobile infantry in the modern period but also mounted infantry, naval infantry, airborne infantry, and air assault infantry.
“Before the adoption of the chariot to create the first mobile fighting forces c. 2000 BC, all armies were pure infantry. Even after, with a few exceptions like the Mongol Empire, infantry has been the largest component of most armies in history.”
Infantry also remains the most basic or fundamental unit of war – the proverbial boots on the ground – for achieving strategic objectives, particularly when those objectives are measured in territory.
As such, infantry has not waned in war, albeit it has evolved with technology. Gunpowder saw infantry shift to line infantry tactics, shooting volleys at each other – until modern firepower overwhelmed even that, forcing infantry for its own survival to use “dispersed, maneuver-based, and heavily supported infantry units” as well as combined arms and the paramount importance of cover on the battlefield.
