09-08-2018, 01:48 AM
(09-07-2018, 04:56 PM)Bryan Wrote: The ridge at Ilerda is identified today (at least it was some years ago). Dodge mentions that the historian Rüstow measured that ridge, finding it equivalent to 360 feet in width at the point that Caesar had three cohorts attacking up it (Caes DBC 1.45-46).
Play with the variables of the size of Caesar's cohorts, and do the math. It will describe the possibilities, depending on the size of the cohorts, of the width and depth of each cohort, at least in Caesar's time.
Well, you can google map the ridge (more of a draw, actually); it in fact is a maximum of 150-180 meters, narrowing substantially as one moves up the hill. We have no great sense of where the fighting took place.
One other problem to consider: Caesar's cohorts were severely understrength; at Pharsalus they would be an average of 275 strong, and were probably not much more than this at Illerda (say 300).
I am willing to posit that Caesar's cohorts at Illerda, fighting in a tight spot, occupied c. 50 meters each, while a full strength Imperial cohort (480 men), might perhaps occupy 80-100 meters. This would give a 4/3/3 legion a frontage of 400-500 meters, accounting for gaps between the cohorts. And of course the whole point of having a modular tactical system was to adjust the frontage and depth of the formation to meet the tactical exigency.
