Argyraspides The principle guard infantry of the Seleucid army was the 'Silver-Shields', or Argyraspides. They were a permanently embodied guard unit, which was formed from the sons of military settlers. They were armed in the Macedonian manner with a sarissa and fought in the phalanx formation, much like the other Hellenistic armies of the time. The Argyraspides were probably a corps of about 10,000 men.
Agema of the hypaspists The agema had a full name, the agema of the hypaspists. The absence of mention of them in detailed writings about the Seleucid campaigns may be due to their having retained only the second half of their name, being called the hypaspists. They formed a crack force within the infantry guardsmen corps. There were 1000
argyraspides of the royal guard at the right flank led by the king at the
Battle of Magnesia in 190 BC.
Chrysaspides and Chalkaspides The Seleucid phalanx may have been divided into corps, similar to a manner proposed of the
Antigonid Macedonian army. Polybius's account of the Daphne parade is again the main source, but unfortunately the suriving fragment is only in a single manuscript and bears signs of a miscopying or lacuna. The surviving sentence says that 20,000 "Macedonians" were at the parade, 5,000
chalkaspides ('Bronze-Shields'), and
agryaspides ('Silver-Shields'). The best guess at what the original sentence was by
Georg Kaibel was that there were 20,000 Macedonians, divided into 10,000 chrysaspides (Greek: Χρυσάσπιδες 'Golden-Shields'), 5,000
chalkaspides, and the rest (the other 5,000)
agryaspides. The existence of a separate corps of Golden-Shields is supported by a reading of
1 Maccabees that poetically refers to "shields of gold and brass" and some other scattered references in Greek literature, although is contested by some such as
Nicholas Sekunda who argues that no such division existed, and the Seleucid phalanx in general were called 'silver-shields'.
'Romanized' infantry In 166 BC, at the Daphne Parade under Antiochus IV, the Argyraspides corps is only seen to be 5,000 strong. However, 5,000 troops armed in the Roman fashion are present and they are described as being in the prime of their life, perhaps denoting their elite nature. It is possible that the missing 5,000 men of the Argyraspides were the 5,000 'Romanized' infantry marching alongside them. The training of a segment of the royal guard in "Roman' methods was probably down to several factors. Firstly, Antiochus IV had 'spent part of his early life in Rome and had acquired rather an excessive admiration for Rome's power and methods". Secondly, the future wars that the Seleucids might be fighting would probably be in the eastern satrapies against mobile enemies and other large areas of land. Training troops in this way would add to the overall efficiency and capability of the army and make it more manoeuvrable. 'Romanized' troops were probably active in suppressing the
Maccabean Revolt, such as their success at the
Battle of Beth Zechariah in 162 BC. The true extent of the adoption of Roman techniques is unknown, some have suggested that the infantry are in fact more likely to be
Thureophoroi or
Thorakitai, troops armed with an oval shield of the Celtic type, a thrusting spear and javelins.
Citizen militia There was a militia, at least in Syria. They were from the Greek cities who had no specific role within the regular army. We do not find the militias involved in the great campaigns before the general decline of the kingdom, which occurred in the latter half of the second century BC. By then, many important military settlements had fallen to
Pergamon and
Parthia. In 148 BC, at the Battle of Azotos against the Maccabees, the Seleucid army was called the 'Power of the Cities', probably owing to the high proportion of citizen militia mobilized from the coastal cities. Citizens of Antioch played a major role in the overthrowing of
Demetrius II Nicator. Demetrius, having taken the throne, decided to disband the majority of the regular army and reduce its pay by a large amount. In place of the regular army, Demetrius' power rested with his Greek, especially Cretan, mercenaries in what was known as the 'Cretan Tyranny'. Not long after, the majority of the citizen militia was wiped out in
Antiochus VII's disastrous Parthian War of 129 BC. Certain ethnic contingents, be they vassal or mercenary, were of considerable use. For example, Thracian mercenaries along with Mysian, Cilician, Lycian, and Vassal troops from the mountainous areas of the empire were used by Antiochus III in conjunction with
Thorakitai in his storming of the Elburz range in 210 BC. The Persian and Iranian troops were most likely of a higher professional military standing than most of the other contingents, as they are seen on garrison duty throughout the empire. The absence of auxiliaries from the army of Antiochus IV may have contributed to its strength. Making up for the loss of ethnic contingents, the army was supplemented by mercenaries, who were more experienced and better trained. The Thracian and Galatian mercenaries at Daphne would have been of good use in campaigns in the rough, hilly terrain. For example, the arms and equipment of the Thracian troops allowed the individual soldier greater mobility and freer action in hand-to-hand combat than a phalangite could adopt. ==Cavalry==