Let us examine an example to understand the overall role that cavalry played in armies.

Two armies, at the beginning of a campaign, operate on the basis of the intelligence they might have on enemy territory and movements, based off of intelligence such as spies or reconnaissance units. In case of the aggressor, the general might take initiative and move into enemy territory either to force the enemy army which is defending it's state to intercept him before he either reaches the capital or an objective of strategic and tactical import, or move in to take a strategically useful and tactically defensive position, therefore taking the strategic initiative and the tactical defensive and using defensive offense in order to force the defender to fight a battle in his own territory on a field of the attacker's choosing. Ofcourse, these examples are a representation of the circumstances that led to a number of battles in the Indian subcontinent, such as the Battle of Panipat or the Battle of Khanwa or the Battle of Tarain, and indeed in real life there's a multitude of variations in which these scenarios played out and even entirely different scenarios did take shape too, but in order to limit the parameters of this discussion let's try and focus on the above scenarios to gain an understanding of the non-combat aspects of cavalry in armies.

Now, let us try and understand how these armies might have moved. In one of the examples mentioned above, the Battle of Panipat, Babur who was the commander of the Mughal forces made use of his light horse archers that served as excellent vanguard and reconnaissance units to scout ahead and report on the enemy locations and movements. He realised that the flat plains before the small town/village of Panipat, was an excellent location to take a defensive position and utilise his wagon fort and tulughma tactics. In the coming battle of Panipat, he scored a victory by seizing the strategic initiative and taking a tactical defensive. However, such scout formations could not be sent too far ahead of an army's main column where the commander and his infantry and artillery train were positioned. Finally was an army's rearguard, which was a means of securing the rear and avoiding being trapped in ambushes or surprise attacks in the first place.

Therefore, armies didn't have pinpoint locations of their enemies before coming fairly close to each other. The reconnaissance abilities of an army played an incredible role in eliminating the fog of war to a certain extent and giving the main column of the army time to prepare for an encounter, and even the reconnaissance itself was limited by the fact that it had to maintain a minimum level of proximity with its main column, in order for intelligence to be conveyed in a fairly efficient and orderly fashion. Hence, a general's movements were informed by intelligence gained, his ability to take initiative and his understanding strategy and tactics.

Cavalry played a crucial role in campaigns, in communications between the various columns in which an army would march and its base of operations, it's headquarters, its supply stations or the king/general/commander and their capital, in intelligence gathering and in executing maneuver warfare and shock or Steppe tactics. It's vast and varied utility and flexibility as an arm of the military made good cavalry an invaluable asset. From the very moment a campaign began, to making victories decisive, cavalry was important.

Now we can examine how cavalry could be employed in actual combat, how it would be deployed and used once battle of given and the enemy stood accross the field from one's own army. Now ofcourse, the outcomes of battles were determined by other factors apart from the morale or compositions or equipment of the opposing armies. Geography, position, ability of the commanders, supply and strategic considerations came into play. But for now, to understand the function that cavalry served in, let us assume that the Battle is being fought at a location where the two sides have taken positions that don't drastically suite them or place them at a disadvantage.

Before any "actual action" even begins, the screening forces of cavalry allow for infantry on both sides to to their positions, form their line and for the artillery (in medieval to modern eras) to take positions, by discouraging their mounted counterparts from charging into as of yet disorganised infantry columns and formations looking for their right place. During a battle, cavalry on the flanks threatens the enemy with encirclement and should both sides' cavalry engage one another on the flanks the cavalry of the winning side has the opportunity to encircle the remaining enemy forces, therefore forcing the enemy to send in reserves or weaken the centre or if the centre is already engaged, then the cavalry can charge into it's flanks, usually routing it. In cases of a purely cavalry based force facing infantry or more traditional armies with both infantry, cavalry and even artillery (in later eras), cavalry could and did still carry the day on many occasions. Simply put, a well organised, highly motivated and disciplined cavalry force, could and did, charge through disorganised infantry formations, captured or spiked artillery, and defeated their cavalry counterparts.

Examples of such engagements can be found well into the 20th century itself. I'll list a few examples here and then conclude with what could've been the reasons behind the effectiveness of cavalry on the battlefield.