Topos of Barbarians Lacking Siege Engines

[Sean Manning]

Thanks! I don't know the Late Antique writers well. I thought there was a passage along those lines about the Parthians, but so far I can't find it. It may be a modern historian who decided that the Arsacids were ignorant of sieges in comparison to the Sasanids? The late A. Shahpur Shahbazi had that idea ... Enc Iranica "Army i. Pre-Islamic Iran"

The (Parthian) tactic was thus unfavorable to close combat operation, and inefficient in laying siege to forts and walled towns; nor could the Parthians sustain long campaigns, especially in the winter months (Rawlinson, op. cit., pp. 406ff.). Since they lacked siege-engines, the Parthians made no use of Roman machines whenever they captured them (Plutarch, Antony 38). And since the army was composed mainly of the dependants of the āzāts, it had to disband sooner or later and go back to the land and the crops. The Parthian general desired to bring to a close a campaign as soon as possible and return home.
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Unlike the Parthians, however, the Persians organized an efficient siege machine for reducing enemy forts and walled towns. They learned this system of defense from the Romans but soon came to match them not only in the use of offensive siege engines—such as scorpions, balistae, battering rams, and moving towers—but also in the methods of defending their own fortifications against such devices by catapults, by throwing stones or pouring boiling liquid on the attackers or hurling fire brands and blazing missiles (Ammianus Marcellinus 19.5f., 20.6-7, 11).