Cavalry and chariots against infantry

[Nathan Ross]

I keep on asking this, what made the horseman throw his pony on the spears of the infantry?

I posted a couple of examples of this sort of 'suicide attack' by cavalry against formed infantry back here. In both cases (Khushab and Aliwal) the breaching attack seem to have been the work of a single recklessly bravura individual. The second is interesting (if we can trust it!) as it suggests that ordering such an attack was actually not that unusual ("We had to charge a square of infantry").

However, I think we can agree that such frontal attacks by unarmoured cavalry were not a general rule!

The surrounding thread has a lot of interesting debate on this exact question:

Roman Heavy Cavalry Fighting Techniques

In particular, some of the ideas about Cataphract and Clibanarii tactics are useful here. Both types of cavalry seem expressly intended to break through infantry (as a successor to the Persian chariot, perhaps?). The Parthian attack at Carrhae involved large numbers of horse archers, and only when the arrows had caused the Roman formation to buckle or thin were the heavy cavalry sent in, presumably to exploit any breaches in the lines.

Nazarius, in Panegyric IV, describes Maxentius' clibanarii at Turin in AD312: "their training for combat is to preserve the course of their assault after they have crashed into (arietare) the opposing line, and since they are invulnerable they resolutely break through whatever is set against them' (IV, 23.4)

Constantine, in this case, defeated the clibanarii by 'drawing [his] lines apart' to 'induce an enemy attack which cannot be reversed'. He then closed his lines again, trapping the enemy horsemen and despatching them with iron-tipped clubs. 'Iron's rigidity did not allow for a change in direction of pursuit'. (Ibid, 24.2)

This suggests that the clibanarii were directed in particular at what appeared to be weak points or breaches in the opposing line*, that they advanced in tight 'rigid' formation at a steady speed, and were supposed to barge through the weakened enemy formation by force and impetus, presumably using their lances at close range to push men back from the breach. I suppose it's possible that the head armour of the horses acted something like blinkers, preventing them from shying or rearing at the sight of the infantry line, and forcing them on into and through whatever appeared as an opening ahead of them.

(* As has been said before, in the case of these very heavy cavalry, the terrifying effect of an attack could have been enough to open such a breach, of course! Even if forced to a halt, a mass of panicking armoured horses and men with long lances would have presented a formidable challenge to an infantry line. Only the most resolute men could have stood their ground against it.)