THE STRENGTH OF THE PERSIAN ARMY AT ISSOS
Posted: Wed Jan 20, 2010 3:50 pm
So , Aubrey de Selincourt in his translation of Arrian for Penguin Classics (footnote 20 p115) ; can such a counsel of despair be truly justified? It will be argued here that the matter is by no means so obscure.‘Plutarch gives the same number [six hundred thousand], Diodorus and Justin four hundred thousand, and Curtius 250,000. All these numbers are fantastic, but we cannot now discover the truth.’
D W Engels has already demonstrated the method, ‘Alexander the Great and the Logistics of the Macedonian Army’ Appendix 2, yet, strangely, no one has applied it to his Persian opponents. Engels demonstrates that one can use the known numbers of Alexander’s army, and the measurable constriction of the Pass of the Pillar of Jonah coupled with the calculated marching rate to arrive at the length of time Alexander has to reach the Pinaros and hence the identity of that stream.
It follows that if we can arrive at the length of time Dareios had to cross the similarly restricted Amanic Gates we can extrapolate the number of men he could have had with him.
The precise position of Dareios’ camp at Sochoi is not established its general location is and it lies sixty-five miles from Issos. Analysis of the marches of both Alexander and Xenophon result in an average daily march of fifteen miles per day. Xenophon’s evidence is especially useful as like Dareios, Cyrus the Younger was marching with an army of both Greeks and natives yet attains the same average march as Alexander.
Despite sending a large baggage train on to Damascus Dareios had not shorn his column of its impedimenta for the Royal Mother, Wife and children complete with attendants were captured after the battle; there is no reason to argue that this was a flying column and allow a more rapid advance.
We can be sure that the Persian march began on the same day that Parmenion’s troops were withdrawn from the passes into the Amuq Plain to rejoin the main army. Had the Persians moved prior too this they would have been observed and Alexander would not have been surprised by their move north, as he clearly was. A later move would not allow enough time for the march, since we have discounted any increase in rapidity.
Engels recognises that the four days that this allows Dareios is probably too little time for the march and posits a day’s delay for Alexander at Issos and we must accept this as the four days are just enough to reach the Pinaros were there no constricted pass to cross. This additional day is the time that Dareios has to cross the pass, then.
The Amanic Gates are at least as restricted as that of The Pillar of Jonah which will allow four men or two horses abreast. Alexander crossed with the cavalry to the rear whereas the Persian cavalry probably led their column, no advantage in speed would have accrued, however, as they must have crossed the Pass at a walk if not leading their mounts on foot.
Allowing the Greek Mercenaries the same 1m spacing as the Macedonians at three kmph 12,000 would cross each hour, native troops were probably in looser order say, 1.5m so 8,000 each hour while the cavalry needing a depth of three metres would cross at an hourly rate of 2,000. Exact hourly divisions are obviously a fudge but provide a useful base from which to work.
We must now estimate the length the Persian marching day. Whilst Curtius tells us that they it was their custom to commence the march later in the day than the Greeks the fact that they achieve the same daily march rate must mean that they marched for the same length of time about eight hours. In Cilicia in November there are eleven hours of daylight, the first would be taken up with the pre-march preparations leaving two for setting up camp at the end of the day.
We must now make a guess at the proportions of the troops crossing. We know that there were Greeks, Kardaka, cavalry and light troops as these are all mentioned in the battle descriptions. The 2:1 ratio of Kardaka to Greeks should be retained and it follows from Demosthenes’ taunt that the Persians outnumbered Alexander in cavalry, this is clear from Alexander’s declining the prospect of battle on the plains too. Since the Macedonians had c. four thousand we might allow the Persians six thousand more would take too long to cross the pass. These would take three of our eight hours, 12,000 hoplites one more and 24,000 Kardaka a further three, leaving an hour for the Royal ladies and some lights 8,000 for the sake of argument.
The next day more levies (up to 64,000) can continue to cross but they will arrive during the day of battle exhausted by their forced march.
We can control these findings by comparison with the frontages of the Macedonian line. The Macedonian infantry was faced by the Greeks and the Kardaka, but if as I have argued (‘The Break in the Macedonian line at Issos’) the Greeks actually charged into the flank of the Hypaspists it follows that they and half the Kardaka faced the Macedonian infantry with Alexander and the Companion Cavalry striking the junction of the Greeks and the Kardaka. The Macedonian line works out to about 1500m so the Greeks occupied 750m eight deep yields only 6,000 which is surely too low, given the force of the Macedonian phalanx a depth of sixteen may have been adopted which gives the same 12,000 posited above. Similarly, there will be 24,000 Kardaka.
I would not pretend that these figures are written in stone but they do show that the number of Greeks has been greatly exaggerated, Arrian has 11,000 surviving the battle! A patent nonsense if the force was a mere 12,000. The maximum number yielded of 108,000 infantry and 6,000 cavalry is possible, the largest recorded ancient force being 120,000. This is an absolute maximum though and many of the troops here-designated lights are probably better considered armed servants. It is also apparent that only 18,000 men had any combat value supporting the evaluation of both Amyntas and Charidemos.