The Battle of Mursa Major (Re-themed): A Polemos SPQR refight

Issue 95 of Wargames, Soldiers & Strategy magazine features the Late Roman Army at war.  As a bonus, there is an additional scenario on the website for free download, which focuses on the Battle of Mursa Major 351AD.  I hadn't heard of this battle before, although I did know that there had been a war in which Constantius II had defeated Magnentius.  Anyway, it seemed a very straightforward battle to re-fight.

I don't have any Late Roman armies but I figured that I could transport the scenario to somewhere between 50BC and 50AD and merely substitute Gauls for Franks. I used the Polemos SPQR rules:

The Terrain:
The instructions for the terrain are very simple: one river (the River Drava) on one side of the table, with a few scattered woods elsewhere on the table.

The Forces:

Western Forces:

Commander: Magnentius (Average)



4 bases of Cavalry (Trained, Formed)
2 bases of Gallic Cavalry (Trained, Elite, Unformed)
4 bases of Legionaries (Trained, Armoured, Formed)
4 bases of Tribal Foot (Raw, Unformed)
3 bases of Tribal Foot (Trained, Unformed)

Notes: The Raw Tribal Foot are actually Limitanei, so poor quality formed troops of some sort would probably be more accurate; any of the Trained-Formed troops could have been classed as Veteran

Eastern Forces:

Commander: Constantius II (Average)



3 bases of Cavalry (Trained, Armoured, Formed)
2 bases of Gallic Cavalry (Trained, Elite, Unformed)

2 bases of Gallic Cavalry (Light Horse, Raw, Unformed)
2 bases of Numidian Cavalry (Light Horse, Trained, Unformed)
5 bases of Legionaries (Trained, Armoured, Formed)
5 bases of Tribal Foot (Raw, Unformed)
4 bases of Auxiliaries (Trained, Armoured, Formed)

Notes: The armoured cavalry should really have been cataphracts.  2 bases of the Light Horse can be Horse Archers.  All classifications are speculative - the armoured cavalry could be veteran and or elite.  The legionaries and/or auxiliaries could be veteran.  The same comments for the Raw tribal foot above apply here too.  Constantius II could be rated as Good.

The Set-Up:

View from behind the Western Army, the River Drava to the left.

And the view from the Drava across the lines of battle

A view of Constantus II's legionaries (left) and auxiliaries (right) with him personally leading his armoured cavalry behind

Gallic Noble Cavalry

Magnentius' infantry: Tribal foot to the left, legionaries to the right

Another shot of the legionaries, next to some of the Roman cavalry

Magnentius' Legionaries are ready for battle

The better-trained Tribal foot are in the deeper column to the left

Another view of Constantus II's legionaries

...and his regular auxiliaries

whilst he leads his armoured cavalry in person

The Battle:

Magnentius, feeling his numerical inferiority, declines to advance, so Constantus II makes the first forward moves

Gallic cavalry and infantry join the move forward

As do the light horse on Constantus' right-wing

The wider view of the advance

As Constantus II's troops close (top), Magnentius manouvres part of his line to try and create some local superiority

The Light Horse go quite wide in their flanking move...

The Gallic cavalry reach a stand-off on the other flank

Constantus II stops the advance of his legionaries and auxiliaries to allow his tribal foot to catch up and employ his superior numbers

The view along the lines...

The light horse moves slowly through the woods on Magnentius' left-flank to try and turn the Gallic cavalry out of its position

The wider view

And at the moment of impact! Constantus II's troops charge...

The majority of the legionaries failed to charge, excepting the unit on the left which has contacted Magnentius' cavalry; some of the auxiliaries have plunged into Magnentius' legionaries.

Light horse and Magnentius' reserve cavalry face off against each other

Battle is joined in earnest: signs of disorder appear in the ranks of Magnentius' cavalry and legionaries

The ebb-and-flow of battle; the tribal foot clash - Magnentius in person leads the pick of the tribal foot with success

The forces of Magnentius are pushed back further and casualties mount...

Magnentius' men put in their own charge against the auxiliaries, who are pushed back in disorder

The fighting between the tribal foot contingents continues...

Magnentius' leads the Gauls into battle with aplomb and their opponents become severely shaken

The light horse continue to plod slowly through the trees...

A group of Magnentius' tribal foot is on the verge of giving way...

But the warriors facing Magnentius himself are already beginning to run away

More of Constantus II's tribal foot are running (top-left) and more are about to join them (centre, see the casualty markers)

Some of Magnentius' cavalry flee to the rear (bottom-centre), whilst the infantry fight still rages

Some of Magnentius' legionaries have been defeated, more are wavering...

Magnentius' tribal foot are hard put to it...

But Magnentius and the Gauls have broken through the centre and their opponents run for the cover of the trees

Repaid in reverse here...

The remainder of Magnentius' Roman cavalry charges, ignoring the numerical disparity and getting the better of the initial exchange...

Despite the heavy casualties, Magnentius' legionaries begin to push Constantus' auxiliaries back!!

After being harassed by some more-or-less ineffective skirmishing, Magnentius' reserve cavalry trap the light horse by the river and begin to slaughter them

The Gallic cavalry charge on the other flank: some of Magnentius' men get the better of the affair...

The other half refused to charge, however.

Magnentius cavalry pursue the remnants of the routed light horse (note that the pursuing cavalry is considered to be very shaken)

Magnentius' legionaries continue to press their enemies back, despite the losses they had earlier suffered

Numbers begin to tell against the bold cavalry...

Constantus II personally leads forward his cavalry and destroys 1,000 of the gallic foot they had caught whilst in a disorganized pursuit...

The out-of-control Gallic warriors pursue wildly into the woods

As does the Gallic cavalry, pursuing their defeated brethren...

However, the other Gallic cavalry are equally under pressure (although still just about holding on)...

At this point, the morale of Constantus II's army collapsed...victory to the usurper!

Game Notes:
A good fun game which lasted 16 turns (80 minutes of simulated time in about 100 mins of playing time).  The refight seemed nearly as sanguinary as the real thing!  Although there was a fair disparity in numbers, experience with these rules has convinced me that that is of secondary importance: the key tactical skill in this game is timing (since manoeuvre is so hard to achieve) and that, as can be seen above, allows much smaller forces to defeat larger ones.  That initial charge bonus has such an effect that it will allow almost anything - in particular if done by a force with a bit of depth.
The army morale rules are quite interesting in that nothing much is likely to happen at the beginning...then the condition of the army rapidly deteriorates when a force loses over about 25% of its strength.  That said, the initial deployment of Constantus II's forces wasn't the best; the light horse in particular was ineffective but was (partly) caught and slaughtered, which contributed quite heavily to the collapse in morale.  Followers of this blog may have noticed that the formations I am using are getting progressively deeper: the rules seem to really reward that.  But even more important are the pursuit rules.  The vulnerability of tribal foot and cavalry when pursuing is so marked that it becomes the one of the most important tactical "facts" of the game.
Figures as ever by Baccus 6mm.