Could the Persian Empire logistically support an army several million strong?

[Justin Swanton]

Following on Anthony's status quaestionis I sum up the progress of the discussion as follows:

A number of objections were made to the feasibility of the Achaemenid Empire raising, moving and supplying an army as large as 5 million men in a journey from the Hellespont to Greece. Thus far I honestly haven't found any of them to be irrefutable:

1.  It can be assumed the Empire had a population large enough to spare 5 million males of military age and still keep going.

2. The army can march overland without having to form impossibly long columns a few men wide. Examples exist of Persian armies moving cross-country in this fashion.

3. The Hellespont can be crossed over a bridge of ships by several million men in the timespan given by Herodotus.

4. Before Thermopylae the overland route does not have any bottlenecks that cannot be traversed by a broad column.

5. The navy can be assumed to be large enough (800 smallish vessels) to supply an army this size. There are sufficient beaches and offloading can be done quickly enough to deposit several thousand tons of grain each day.

6. The campsites need not be impossibly large and the local water supply is adequate for the needs of 5 million men.

7. The local allied Greeks are capable of supplying the army with an occasional meal without overstraining their resources and the 400 talent supper supplied by the Thasians indicates an army in the millions, not low hundreds of thousands.

8. Maurice as an argument of authority is not conclusive. He has been proven seriously inaccurate in several crucial estimates.

9. Herodotus is too systematic in affirming or implying an army in the millions rather than low hundreds of thousands. If he is wrong then he is guilty of deliberate fabrication, not just vague exaggeration. This makes him completely unreliable as a source, despite the fact he generally has a good reputation among contemporary historians.

Let me know if I've missed anything out.

[Justin Swanton]

Duncan's point though is that Selymbria was capable of falling short of its requirements only if it exported its grain. The law implied that if the city kept all its harvest it would manage in a poor year. The problem then becomes what to do with the excess grain in a normal or good year. This all suggests that a Greek polis like Selymbria on average produced more than it needed (their law had left them with a large surplus they now had to dispose of). Certainly enough to supply a large passing Persian army with a meal.

The purpose of storing grain in a polis is that most years you're OK. But a bad year might destroy you. Even a 5% shortfall can lead to price gouging, riots and violent political change.
The fact that a city banned exports shows how important this is, and how close to the edge they habitually sailed.
If you look at the example Duncan gave, "On one occasion, however, they were in need of funds; and as they possessed large stores of grain....."
So it was a one off.
It wasn't a large surplus they now had to dispose of, they were in need of funds and the only way the city had of raising those funds was to sell some of their grain. It was a gamble the city felt prepared to take.
With the funds raised they appear to have gone back to squirrelling away grain again, breathing a sigh of relief that they'd 'got away with it' this once.

Mmm...fair enough. The Selymbria example proves that a polis could produce a surplus for export but doesn't state how often that surplus was produced. So we can't draw any conclusions from it on the general productivity of a Greek polis.

There, backpedalled. 

[Jim Webster]

4. Before Thermopylae the overland route does not have any bottlenecks that cannot be traversed by a broad column.

This is your opinion, it is not something that is widely agreed. Personally I would put Gallipoli down as a bottleneck on the strength of the  opinion of people who have tried to move troops through it, or were used to moving troops and didn't like the ground

[Jim Webster]

6. The campsites need not be impossibly large and the local water supply is adequate for the needs of 5 million men.

This is again not something agreed, it is your opinion but some of us express doubts. Personally I don't think Xerxes had a snowballs chance in hell in getting an army of 5 million strong across the bridge and to Thermopylae

[Jim Webster]

Following on Anthony's status quaestionis I sum up the progress of the discussion as follows:



Let me know if I've missed anything out.

well the fact that I for one don't actually agree with any of the above 

[Justin Swanton]

4. Before Thermopylae the overland route does not have any bottlenecks that cannot be traversed by a broad column.

This is your opinion, it is not something that is widely agreed. Personally I would put Gallipoli down as a bottleneck on the strength of the  opinion of people who have tried to move troops through it, or were used to moving troops and didn't like the ground

The military men who don't like the ground all work from the assumption the army sticks to roads/tracks and the countryside hasn't been cleared to permit cross-country marching. They need to be asked the question: "If we spend 4 years clearing away trees, difficult undergrowth and other obstacles, is there a way through the Gallipoli peninsula that would permit a column 600 yards wide to advance?"

[Justin Swanton]

Following on Anthony's status quaestionis I sum up the progress of the discussion as follows:



Let me know if I've missed anything out.

well the fact that I for one don't actually agree with any of the above 

10. The fact that Jim Webster does not endorse a 5-million man army might not constitute a conclusive refutation even though he has excellent things to say and I've enjoyed his articles in Slingshot. 

[Duncan Head]

If you look at the example Duncan gave, "On one occasion, however, they were in need of funds; and as they possessed large stores of grain....."
So it was a one off.

Actually, we don't know that. How did (pseudo-)Aristotle know about this event? Probably he, or his source, saw an inscription in Selymbria's agora recording the decree for the "compulsory purchase" and the free export - that's how a lot of these things pass into wider knowledge, a Greek polis will set up an inscription commemorating almost anything. And there could have been dozens of such decrees. So obviously not an annual event, but not necessarily all that rare, either.

[Erpingham]

I don't want to enter into tit-for-tat but I assume you've abandoned the cautious, reasoned approach for deliberate provocation to try to refocus our minds, so here goes.

1.  It can be assumed the Empire had a population large enough to spare 5 million males of military age and still keep going.
Not impossible but we lack evidence that this happened or that this military capacity could be deployed in one place.

2. The army can march overland without having to form impossibly long columns a few men wide. Examples exist of Persian armies moving cross-country in this fashion.
The "columns a few wide" are a straw man argument.  Cross country movement is assumed by all parties as there are no proper roads.  Behaviour of later Persian armies in open plains has disputable relevance
3. The Hellespont can be crossed over a bridge of ships by several million men in the timespan given by Herodotus.
Probably true, though has no bearing on numbers crossing

4. Before Thermopylae the overland route does not have any bottlenecks that cannot be traversed by a broad column.
This seems to be disputed

5. The navy can be assumed to be large enough (800 smallish vessels) to supply an army this size. There are sufficient beaches and offloading can be done quickly enough to deposit several thousand tons of grain each day.
You can only make this statement by ignoring much of what has been written above.  It is doubtful that sufficient supplies could be unloaded over beaches with the regularity and quantity given.  We have no independent evidence of the size of the fleet and 800 ships is an estimate based on army size, not an independent confirmation of it

6. The campsites need not be impossibly large and the local water supply is adequate for the needs of 5 million men.
This statement can only really be made by ignoring arguments made.  The water issue has only been tackled by stating Maurice made a major miscalculation of the rate of flow in Asia Minor, so therefore all issues modern armies on the march had with watering horses can be dismissed


7. The local allied Greeks are capable of supplying the army with an occasional meal without overstraining their resources and the 400 talent supper supplied by the Thasians indicates an army in the millions, not low hundreds of thousands.
The first part of the statement is true (because it's vague), the second part relies on a figure provided by Herodotus so can't be used to confirm Herodotus' figures are correct

8. Maurice as an argument of authority is not conclusive. He has been proven seriously inaccurate in several crucial estimates.
Maurice is one of many modern estimates of the size of the army which dispute Herodotus' figures.  He seems to have taken on a prominence because he approached the march as a military exercise as opposed to a papers and pencil (or calculator) one.  Most of the areas where he raised issues have not been satisfactorially bottomed even if he may not be correct in all details.

9. Herodotus is too systematic in affirming or implying an army in the millions rather than low hundreds of thousands. If he is wrong then he is guilty of systematic fabrication, not just vague exaggeration. This makes him completely unreliable as a source, despite the fact he generally has a good reputation among contemporary historians.
He seems to have had a worse reputation among Ancient historians than modern ones.  He does seem to have thought about his numbers but seems to have been the victim either of propaganda or a "barbarian horde" trope, which in this setting would be mutually reinforcing

Let me know if I've missed anything out.
Quite a bit but lets not get carried away

[Erpingham]

10. The fact that Jim Webster does not endorse a 5-million man army might not constitute a conclusive refutation even though he has excellent things to say and I've enjoyed his articles in Slingshot. 

11. Just because Justin and Patrick say something is so don't make it so either, even though lots of interesting byways have been explored and calculations made.

[Jim Webster]

4. Before Thermopylae the overland route does not have any bottlenecks that cannot be traversed by a broad column.

This is your opinion, it is not something that is widely agreed. Personally I would put Gallipoli down as a bottleneck on the strength of the  opinion of people who have tried to move troops through it, or were used to moving troops and didn't like the ground

The military men who don't like the ground all work from the assumption the army sticks to roads/tracks and the countryside hasn't been cleared to permit cross-country marching. They need to be asked the question: "If we spend 4 years clearing away trees, difficult undergrowth and other obstacles, is there a way through the Gallipoli peninsula that would permit a column 600 yards wide to advance?"

Not the military men I read. They know how troops move because they've moved them which in my eyes is a pretty big plus for them. If the locust formation was such a success, it would have been used more widely

[Justin Swanton]

I don't want to enter into tit-for-tat but I assume you've abandoned the cautious, reasoned approach for deliberate provocation to try to refocus our minds, so here goes.

Not at all. You gave your own position in your summing up: "I know that all the figure work has confirmed to me that the orthodox view is closer to a practical reality at the same time pointing up the flaws of some of the more minimal estimates, like Delbruck or Young" - so I gave mine. But whether I think 5 million men is reasonable or whether Jim thinks it's tosh is neither here nor there for the purposes of the discussion. I'm quite happy to separate my own opinions from the direction the arguments take and change my mind if necessary (I just did so over the Selymbria example).

To sum up the discussion in terms that does not include my personal convictions: whilst the majority of posters keep to the position of an army below half a million, the arguments and facts put forward do not seem to have conclusively ruled out the possibility of an army of several million strong though most posters feel these arguments and facts have not conclusively or even substantially proved the big army hypothesis either.

Sounds OK?

[Justin Swanton]

10. The fact that Jim Webster does not endorse a 5-million man army might not constitute a conclusive refutation even though he has excellent things to say and I've enjoyed his articles in Slingshot. 

11. Just because Justin and Patrick say something is so don't make it so either, even though lots of interesting byways have been explored and calculations made.

Agreed.

[Jim Webster]

If you look at the example Duncan gave, "On one occasion, however, they were in need of funds; and as they possessed large stores of grain....."
So it was a one off.

Actually, we don't know that. How did (pseudo-)Aristotle know about this event? Probably he, or his source, saw an inscription in Selymbria's agora recording the decree for the "compulsory purchase" and the free export - that's how a lot of these things pass into wider knowledge, a Greek polis will set up an inscription commemorating almost anything. And there could have been dozens of such decrees. So obviously not an annual event, but not necessarily all that rare, either.

I'd suggest that the fact they set up an inscription meant that it wasn't the default option.
It's something that is going to fluctuate with time. A series of bad harvests and exports might be banned for a number of years.

But the bit that interested me was it was done because they were in need of funds. Whatever overrode their desire to ban exports was entirely pragmatic, they needed the money.
Admittedly they might have needed the money to fund a really good annual dinner for the magistrates but it's still a priority. 

[Imperial Dave]

I've just trawled through the last 20 or so pages to catch up.......lively thread