Late Roman Army during the 5th century

[Nathan Ross]

The Panegyrici Latini 12:3 claims that Constantinus crossed the Alps, with barely ¼ of his army, against 100,000 enemies.

The panegyric actually specifies that Constantine's expeditionary force was 'fewer than forty thousand men', and notes that Alexander the Great believed a army larger than this was not an army but a mob!

I have lately been trying to reconstruct the army structure of the Tetrarchy and the post-Tetrarchan civil wars. It is incredibly frustrating.

A while ago, just out of interest, I tried to work out what sort of units and army numbers might have been available to Constantine in 312, based on earlier estimates and the tetrarchic-looking units mentioned in the ND. It was far from a scientific or rigorous analysis (!), but I remember coming up with a figure of around 120,000. So perhaps if Constantine led a force of 30-35,000 or so into Italy, and allowing for a little panegryical exaggeration, it wasn't too far short of a quarter of his entire army.

All the competing emperors of this period were probably conscripting as hard as fast as they could, and enlisting any barbarian groups they could too, so the army as a whole would be quite swollen. Maxentius in particular appears to have raised a large number of men in southern Italy, Sicily and North Africa. The quality of these new units (or whatever they were) may have been debatable, and none seem to have survived into the later establishment, but by leaving his borders undefended and centralising his force he could have put 100,000 men onto the battlefield (though they would have been something more like Alexander's 'mob'!)

So if all four emperors of the day were able to muster comparable forces to Constantine, the total combined 'Roman' army in 312 may have been close to half a million. But, like the civil wars of the late Republic, this was a time of crisis and expediency.

However, this is a bit of a digression from the late 5th century! :neutral: