Further interpretations of interpenetration

[Erpingham]

I'm not sure being bursting through the enemy is quite the same.  I think the usual wargamer definitions involve units on the same side.

Talking of which, though, you may get non-consensual break throughs of troops on the same side.  Men-at-arms through crossbowmen and archers seems to have happened in several medieval battles (Courtrai, Crecy and Montlhery, for example).

[Imperial Dave]

just a quick two seconds on Nick's post.....it is an interesting observation and I wonder how many occurrences of this type of thing happened in ancient battles and what the 'set up' of the burst through troops was to 'allow' this

[Erpingham]

Much depends what we are counting.

Does opening lanes for chariots to pass through, where they are mugged by troops behind, count?

What about breaking a first line and going through the gap, only to be stopped by a second, as at Strasbourg?

I can think of a few medieval burst throughs, where the burst through force survived.  English at the Standard, English at Verneuil, English at first day of Valmont (this last one seemingly because their line was too thin).

[Prufrock]

I haven't seen Chris's article yet, but one thing that I have wondered about is how consistent the ability of troops to perform a particular manoeuvre was. Do we tend to take an example of a capability at one time and then - unless a source says otherwise - assume that that capability was generally present, when it may in fact have been specific to a particular occasion, commander, army, etc.? 

Obviously, rules-writers get around this uncertainty by limiting certain manoeuvres to defined troop classes (e.g., veterans), by introducing scenario-specific rules, by making difficult moves a drain on command points, or by inviting players to petition the dice gods to adjudicate through a manoeuvre/leadership test.

I think I'm probably in favour of the dice gods model at a tactical level and a defined troop classes or command points model at grand-tactical end.

Apologies if I've gone off on a tangent here...

[Imperial Dave]

I haven't seen Chris's article yet, but one thing that I have wondered about is how consistent the ability of troops to perform a particular manoeuvre was. Do we tend to take an example of a capability at one time and then - unless a source says otherwise - assume that that capability was generally present, when it may in fact have been specific to a particular occasion, commander, army, etc.? 

Obviously, rules-writers get around this uncertainty by limiting certain manoeuvres to defined troop classes (e.g., veterans), by introducing scenario-specific rules, by making difficult moves a drain on command points, or by inviting players to petition the dice gods to adjudicate through a manoeuvre/leadership test.

I think I'm probably in favour of the dice gods model at a tactical level and a defined troop classes or command points model at grand-tactical end.

Apologies if I've gone off on a tangent here...

nope, no tangents at all! 

[Erpingham]

In the absence of hard evidence, I'm trying to think how things might have happened and how things might have gone wrong.

Should interpenetration be limited to historically recorded armies?  Tricky.  I think light infantry pass through should be pretty generic as it is common in many times and places.  Cavalry through infantry I'm less sure.  We know some regular practitioners (e.g. Imperial Romans, Byzantines) so maybe other drilled forces?  But then medieval infantry did it on occassion, and they weren't drilled troops.  Heavy infantry through heavy infantry - other than Romans what evidence do we have?  So make this one Republican Romans only (I don't think there is evidence of Imperial line relief).

What could go wrong?   I suspect this needed some degree of freedom from interference, especially for the undrilled.  I also suspect disorder on the part of either party to the transaction would mess things up.  So neither party in contact or disordered?  Maybe special rule again for Romans, though I suspect they line exchanged in lulls, using their training to do the switch before the enemy could respond.

Automatic, diced for or special manouevre?  I'd say not automatic, with some sort of test, or use of PIPs or having a special card - whatever your rules use to limit initiative like this.

[Imperial Dave]

I would be in favour of a disorder severity penalty depending on the type of troops trying to interpenetrate, their drill level and their proximity to the enemy. In such a system, in theory you could have close order troops being able to interpenetrate with other close order but only if done out of charge reach/ZOC and then causes a level of disorder that takes a bound to correct etc

on the actual live mechanism, someone mentioned about lulls in battle and the potential for lines to separate by mutual agreement thus allowing rotation of lines and/or bodies....?

[RichT]

The trouble (or troubles) with reading a battle account, seeing an instance of interpenetration, and trying to fit it into your rules, is/are a) you can end up with some very complicated rules and b) as we suggested in the pila thread, battle descriptions might mention something because it is atypical, not because it is typical. I might be inclined to try to limit it to where there is some definitely identified drill or doctrine.

Another approach is to think what outcome we are hoping to reproduce in terms of realistic player behaviours. We know for sure that armies often formed in two lines, LI in front, HI behind. So the rules are going to have to allow the LI to retire back through the HI or no player will ever put them up there but will find some other use for them. Similarly with Roman triplex acies - there has to be some sort of line relief/replacement ability, or there's no incentive to put them in three lines. Where armies aren't seen to form in multiple lines historically there may be no need to allow interpenetration, which might otherwise encourage players to use an unhistorical number of lines.

I don't know where this leaves Medieval three battle arrays, other than making their own sets of rules and stop making things complicated for proper Ancients.

[Erpingham]

I don't know where this leaves Medieval three battle arrays, other than making their own sets of rules and stop making things complicated for proper Ancients.

So, three lines of Romans good, three lines medievals bad? 

Medieval column of divisions armies are awkward at the best of times.  I've been reading a few Italian battles recently and stacking units one behind the other was common.  But we get reinforcements piling in from divisions behind, we get parts of lines going out sideways and launching flank attacks and all sorts of odd things happening.  Medieval descriptions do give the impression that cavalry in particular didn't stay in their divisional lines but attacked and withdrew in smaller groups.  Somehow these moved through and round other divisions.  If we go to the later end of Italian practice we find Bracceschi tactics, where squadrons rotated in and out of the line to take breathers, which seems the ultimate version of this.

On a more mixed arms basis, medieval armies often followed the same model as their ancient forebears (they'd all read Vegetius, after all ) and put light infantry to the fore, then withdrawn these when it was time to send in the close fighters.  If we look at hastings, the archers shot first, then the infantry attacked, then there were waves of cavalry attacks as conrois attacked and fell back.  There must, therefore, have been interpenetration of lines here, probably aided by a static enemy, but I don't think the method is described.

[Imperial Dave]

I am of a mind to have the screen in a tabletop battle as part of the mainline troops that are assumed to disappear as lines close but this could be a little one dimensional

[Duncan Head]

Medieval descriptions do give the impression that cavalry in particular didn't stay in their divisional lines but attacked and withdrew in smaller groups.  Somehow these moved through and round other divisions.

They'd invented the element?

[RichT]

So, three lines of Romans good, three lines medievals bad?

Yup, seems fair.

Also I've been wondering where the name 'interpenetration' for this sort of thing comes from - I don't much like it as a term (it's easy to type wrong) and wonder if 'passage of lines' wouldn't be a better thing to call it - there's a whole mass of theory on passage of lines in other eras which while not all directly relevant might make for useful comparative stuff (for example I like the distinction between rearward and forward passage of lines - the former being what skirmish lines for eg do, the latter what cavalry exploiting through infantry do).

Edited as I got forward and rearward the wrong way round. I hate it when that happens.

[Imperial Dave]

is there anything in any military manuals...seems like a stupid question otherwise I'm sure others would have pointed it out by now? Was thinking the Strategikon for instance??

[Andreas Johansson]

is there anything in any military manuals...seems like a stupid question otherwise I'm sure others would have pointed it out by now? Was thinking the Strategikon for instance??

Units of cavalry passing through gaps between other units of cavalry. Maurice's chief concern is that the second line should have gaps that the first line can fall back through, or rally within, if beaten.

Interestingly, the gaps need to be about 1/4 the width of the units that are supposed to fall back through them. A reminder that, again outside 1-1 skrimish games, our units and elements are more rigid than real bodies of men, and we may require a rule for passing through "impossibly" small gaps.

(Actually, even in 1-1 skirmish games, figures, with bases and dynamic poses, are likely to be impossible to physically move through various gaps that a real soldier would find trivial to negotiate.)

[Imperial Dave]

its a good point Andreas, we tend to view 'gaps' as a physical barrier in the main if narrower than an element or unit