The Makedonian phalanx -- why such depth?

[Paullus Scipio]

Paullus Scipio wrote: it is not clear here whether "Hetaroi" refers to the Mounted "Companions" or the "Pez-hetaroi/Foot-Companions" but the context would appear to be the latter;( they are launched against the Phalanx) the Agrianes and Balacrus' Thracian javelin-men are clearly light Infantry, referred to elsewhere as well.

Note that the scythed chariots are launched against the Phalanx, and that they are opposed by the light Infantry screen.


Not at all: it is abundantly clear that Companion Cavalry is intended.

As I wrote earlier the Agrianes are not posted in front of the phalanx. There is no need to attempt to extrapolate from Arrian’s battle description the whereabouts of the Agrianes for he makes very plain where Alexander placed them (3.12.1 ff):
Next to the royal squadron on the right wing, half of the Agrianians, under the command of Attalus, in conjunction with the Macedonian archers under Briso’s command, were posted angular-wise in case they should be seized anyhow by the necessity of deepening the phalanx, or of closing up the ranks. Next to the archers were the men called the veteran mercenaries, whose commander was Cleander. In front of the Agrianians and archers were posted the light cavalry used for skirmishing, and the Paeonians, under the command of Aretes and Aristo. In front of all had been posted the Grecian mercenary cavalry under the direction of Menidas; and in front of the royal squadron of cavalry and the other Companions had been posted half of the Agrianians and archers, and the javelin-men of Balacrus who had been ranged opposite the scythe-bearing chariots.


The hetairoi referred to are clearly and unequivocally the Companion Cavalry and not pezhetairoi as your stretch of the source material would have it. It is evident that Darius’ intention was to neutralise or seriously hamper the Macedonian strike weapon – the Companion Cavalry and its king. Alexander prepared his dispositions accordingly. That the line of these chariots also stretched far enough toward the Persian centre so as to charge the far right of phalanx is correct. Arrian explicitly states that these were dealt with by the grooms and the rear ranks of the hypaspists (who had made way for them as instructed).
• Paralus|Michael Park

We need not quibble as to the posting of the light infantry too much – it is clear from all the sources ( and their numbers) that the light infantry screen stretched across part at least of the phalanx, that the Chariots were tackled and largely stopped by the light infantry/javelin -men, but that some at least made it to the phalanx, where they were let through by the opening of gaps……perhaps Hetairoi here means generically both Mounted and Foot companions?
Interestingly, we don’t hear in any of our sources of the scythed chariots going up against the Mounted Companions….only the Phalanx….. Perhaps Darius intended the scythed chariots to disrupt Alexander's Mounted Companions, but his oblique rightward movement took them clear of the chariot lanes....it is suggestive that the Agrianes and archers directly in front of the Mounted Companions don't seem to have taken part, but rather the javelin-men of Balacrus to their left - indeed Arrian specifically tells us that these latter "stood facing the Persian scythed chariots".

However,we need only be concerned with the movements of the Phalanx here, and they clearly opened 'gaps' in the line, not as you suggested, moved into 'open' order. Xenophon's "Ten Thousand" had dealt with scythed chariots in exactly the same way some 70 years earlier at Cunaxa, with exactly the same result