Question about the Roman \'wedge formation\'

[Nathan Ross]

Vikings were known to use roughly the same formation, the "SVINEFYLKING" (Pig-head)

I understood the viking version to essentially be a ram.

It seems the Roman version was effectively the same, and even went by the same name in the later era:

A wedge (cuneus) is the name for a mass of infantry who are attached to the line, which moves forward, narrower in front and broader behind, and breaks through the enemy lines, because a large number of men are discharging missiles into one position. Soldiers call this tactic a 'pig's head' (caput porcinum) - (Vegetius, III,19)

Quite possibly the Roman tactic (or just the name for it?) was adopted by Germanic warriors and passed Norse-wards from there. Alternatively, the nickname could have been adopted by the Romans from their enemies... Milner's note to Vegetius mentions that Hannibal used a cuneus at Cannae.

Either way, it seems a common and effective tactic used (as other have noted above) by many armies - nothing complex or mysterious about it, just a mass counter-attack from the centre designed to split an opposing force.

Vegetius also described the 'saw' (serra), but it's nothing like the wedge:

The 'saw' is the name of a formation which is ranged by crack troops before the front, facing the enemy, so that a disordered line may be repaired - (Vegetius, ibid)

Milner quotes the grammarian Festus for an alternative to this (rather opaque) description: To 'fight in saw formation' is said when there is a constant advancing and retreating, no standing still at any time.

So the 'saw' seems to have been a mobile defensive formation rather than an offensive one.

Needless to say, however, Tacitus makes no mention of 'saws' in his description of the Boudica battle. The word he uses is cuneus, meaning 'wedge', a well-known standard Roman battlefield tactic.